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'10' on line 598 looks like a reference Summary: 10 errors (**), 0 flaws (~~), 4 warnings (==), 14 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 1 Network Working Group Jacob Palme 2 Internet Draft Stockholm University/KTH 3 draft-ietf-mailext-attributes-02.txt Sweden 4 Category: Informational July 1995 5 Expires January 1996 7 Common Internet Message Attributes 9 Status of this Memo 11 This document is an Internet-Draft. Internet-Drafts are working 12 documents of the Internet Engineering Task Force (IETF), its 13 areas, and its working groups. Note that other groups may also 14 distribute working documents as Internet-Drafts. 16 Internet-Drafts are draft documents valid for a maximum of six 17 months and may be updated, replaced, or obsoleted by other 18 documents at any time. It is inappropriate to use Internet- 19 Drafts as reference material or to cite them other than as 20 ``work in progress.'' 22 To learn the current status of any Internet-Draft, please check 23 the ``1id-abstracts.txt'' listing contained in the Internet- 24 Drafts Shadow Directories on ftp.is.co.za (Africa), 25 nic.nordu.net (Europe), munnari.oz.au (Pacific Rim), 26 ds.internic.net (US East Coast), or ftp.isi.edu (US West Coast). 28 This memo provides information for the Internet community. This' 29 memo does not specify an Internet standard of any kind, since 30 this document is mainly a compilation of information taken from 31 other RFC-s.. Distribution of this memo is unlimited. 33 Abstract 35 This memo contains a table of commonly occurring attributes in 36 headings and on envelopes of e-mail messages. The document compiles 37 information from other RFC-s such as RFC 821, RFC 822, RFC 1036, 38 RFC 1123, RFC 1327, RFC 1496, RFC 1521 and RFC 1766. A few commonly 39 occurring attributes which are not defined in RFC-s are also 40 included. For each attribute, the memo gives a short description 41 and a reference to the RFC, in which the attribute is defined. 43 Table of contents 45 1. Introduction 47 2. Use of gatewaying attributes 49 3. Table of attributes 51 3.1 Phrases used in the tables 52 3.2 Addressing information 53 3.3 Envelope and format information 54 3.4 Sender and recipient indication 55 3.5 Response control 56 3.6 Message identification and referral attributes 57 3.7 Other textual attributes 58 3.8 Attributes containing dates and times 59 3.9 Quality information 60 3.10 Language information 61 3.11 Size information 62 3.13 Encoding information 63 3.14 Resent-attributes 64 3.15 Miscellaneous 66 4. Acknowledgments 68 5. References 70 6. Author's address 72 Appendix A: Attributes sorted by Internet RFC document in which 73 they appear 75 Appendix B: Alphabetical index 76 1. Introduction 78 Many different Internet standards and RFC-s define attributes which 79 may occur on Internet Mail Messages and Network News Articles. The 80 intention of this document is to list all such attributes in one 81 document as an aid to people developing message systems or interested 82 in Internet Mail standards. 84 The document contains all heading attributes which the author has 85 found in the following Internet standards: RFC 821 [1], RFC 822 [2], 86 RFC 1036 [3], RFC 1123 [5], RFC 1327 [7], RFC 1496 [8], RFC 1521 [11] 87 and RFC 1766 [12]. Note in particular that heading attributes defined 88 in RFC 1421-1424, "Privacy Enhancement for Internet Electronic Mail", 89 are not included. A few additional attributes which often can be 90 found in e-mail headings but are not part of any Internet standard are 91 also included. 93 For each heading attribute, the document gives a short description and 94 a reference to the Internet standard or RFC, in which they are defined. 96 2. Use of gatewaying attributes 98 RFC 1327 defines a number of new attributes in Internet mail, which 99 are defined to map attributes which X.400 has but which were 100 previously not standardized in Internet mail. The fact that an 101 attribute occurs in RFC 1327 indicates that it is recommended for 102 use in gatewaying messages between X.400 and Internet mail, but 103 does not mean that the attribute is recommended for messages wholly 104 within Internet mail. Some of these attributes may eventually get 105 accepted also for usage within Internet mail, but they are, when 106 this is written (July 1995) not recommended for such usage. 108 Fields defined in RFC 1036 for use in Usenet News sometimes appear 109 in mail messages, either because the messages have been gatewayed 110 from Usenet News to e-mail, or because the messages were written in 111 combined clients supporting both e-mail and Usenet News in the same 112 client. These fields are however not standardized for use in 113 Internet e-mail and should be handled with caution. 115 Fields are given here in the spelling used in e-mail headers. This 116 may sometimes be English, sometimes American spelling. One attribute, 117 "Organisation/Organization" occurs in e-mail headers sometimes with 118 English, sometimes with American spelling. 120 3. Table of attributes 122 3.1 Phrases used in the tables 124 "not for general Used to mark attributes which are defined in 125 usage" RFC 1327 for use in messages from or to 126 Internet mail/X.400 gateways. These attributes 127 have not been standardized for general usage 128 in the exchange of messages between Internet 129 mail-based systems. 131 "not standardized Used to mark attributes defined only in RFC 132 for use in e-mail" 1036 for use in Usenet News. These attributes 133 have no standard meaning when appearing in e- 134 mail, some of them may even be used in 135 different ways by different software. When 136 appearing in e-mail, they should be handled 137 with caution. Note that RFC 1036, although 138 generally used as a standard for Usenet News, 139 is not an accepted IETF standard or on the 140 IETF standards track. 142 "non-standard" This attribute is not specified in any of 143 those referenced RFC-s which are Internet 144 standards, draft standards or proposed 145 standards. The attribute appears here because 146 it is common in e-mail or Usenet News headers. 147 Usage of these attributes is not in general 148 recommended. 150 "discouraged" This attribute, which is non-standard, is 151 known to create problems and should not be 152 generated. Handling of such attributes in 153 incoming mail should be done with great 154 caution. 156 "controversial" The meaning and usage of this attribute is 157 controversial, i.e. different implementors 158 have chosen to implement the attribute in 159 different ways. Because of this, such 160 attributes should be handled with caution and 161 understanding of the different possible 162 interpretations. 164 "for limited use" A so-called "experimental" Internet standard. 165 These should be used only if both parties 166 agree. 168 3.2 Addressing information 170 Original sender. Should in MAIL FROM RFC 821, 171 Internet be empty ("MAIL FROM: RFC 1123: 5.2.9. 172 <>") when sending notifications, 173 and be the list administrator 174 when forwarding from a 175 distribution list. This value may 176 for gatewayed messages contain a 177 chain of hosts to be passed in 178 sequence to reach the original 179 sender (i.e. a relative address). 181 Used to convey the information Return-Path: RFC 821, 182 from the MAIL FROM envelope RFC 1123: 5.2.13. 183 attribute when the message leaves 184 the SMTP environment in which 185 "MAIL FROM" is used. 187 Recipient to which message is to RCPT TO RFC 821, 188 be delivered. Relative address RFC 1123: 5.2.6. 189 was allowed in RFC 821, but later 190 prohibited in RFC 1123. 192 3.3 Envelope and format 193 information 195 All that is inside the envelope. DATA RFC 821, 196 RFC 1123: 5.2.8. 198 Trace of MTA-s which a message Received: RFC 822: 4.3.2, 199 has passed. RFC 1123: 5.2.8. 201 An indicator that this message is MIME-Version: RFC 1521: 3. 202 formatted according to the MIME 203 standard, and an indication of 204 which version of MIME is 205 utilized. 207 List of MTA-s passed. Path: RFC 1036: 2.2.6, 208 not standardized 209 for use in e-mail. 211 Special Usenet News actions. Control: RFC 1036: 2.1.6, 212 not standardized 213 for use in 214 e-mail. 216 Trace of distribution lists DL-Expansion- RFC 1327, not for 217 passed. History- general usage. 218 Indication 220 Which body part types occur in Original- RFC 1327, not for 221 this message. Encoded- general usage. 222 Information- 223 Types: 225 Special informational message. Message-Type: RFC 1327, not for 226 Delivery general usage. 227 Report 229 Controls whether this message may Alternate- RFC 1327, not for 230 be forwarded to alternate Recipient: general usage. 231 recipients such as a postmaster 232 if delivery is not possible to 233 the intended recipient. Default: 234 Allowed. 236 Whether recipients are to be told Disclose- RFC 1327, not for 237 the names of other recipients of Recipients: general usage. 238 the same message. This is 239 primarily an X.400 facility, such 240 disclosure is in Internet mail 241 done via the To:, Cc: and Bcc: 242 heading fields. 244 3.4 Sender and recipient 245 indication 247 Author, approver From: RFC 822: 4.4.1, 248 RFC 1123: 5.2.15- 249 16, 5.3.7. 251 Moderator Approved: RFC 1036: 2.2.11, 252 not standardized 253 for use in e-mail. 255 Sender information inside the Sender: RFC 822: 4.4.2, 256 envelope. RFC 1123: 5.2.15- 257 16, 5.3.7. 259 Main recipients. To: RFC 822: 4.5.1, 260 RFC 1123: 5.2.15- 261 16, 5.3.7. 263 Additional recipients. Cc: RFC 822: 4.5.2, 264 RFC 1123. 5.2.15- 265 16, 5.3.7. 267 Recipients not shown to other Bcc: RFC 822: 4.5.3, 268 recipients. RFC 1123: 5.2.15- 269 16, 5.3.7. 271 In Usenet News: group to which Newsgroups: RFC 1036: 2.1.3, 272 this article was posted. not standardized 273 Some systems provide this field and controversial 274 also in e-mail although it is not for use in e-mail. 275 standardized there. 276 Unfortunately, the field can 277 appear in e-mail with two 278 different and contradictory 279 meanings: 280 (a) Indicates the newsgroup 281 recipient of a message sent to 282 both e-mail and Usenet News 283 recipients. 284 (b) In a personally addressed 285 reply to a message in a 286 newsgroup, indicates the 287 newsgroup in which this 288 discussion originated. 290 Inserted by Sendmail when there Apparently- Non-standard, 291 is no "To:" recipient in the To: discouraged, 292 original message, listing mentioned in 293 recipients derived from the RFC 1211. 294 envelope into the message 295 heading. This behavior is not 296 quite proper, MTA-s should not 297 modify headings (except inserting 298 Received lines), and it can in 299 some cases cause Bcc recipients 300 to be wrongly divulged to non-Bcc 301 recipients. 303 Limitation on where this message Distribution: RFC 1036: 2.2.7, 304 can be distributed. not standardized 305 for use in e-mail. 307 Fax number of the originator. Fax:, Non-standard. 308 Telefax: 310 Phone number of the originator. Phone: Non-standard. 312 Information about the client Mail-System- Non-standard. 313 software of the originator. Version:, 314 Mailer:, 315 Originating- 316 Client: 318 3.5 Response control 320 Replacement for "From:" to which Reply-To: RFC 822: 4.4.3, 321 replies are to be sent. controversial. 322 Unfortunately, the specification 323 in RFC 822 is ambiguous, since 324 some people want this to be a 325 replacement for all recipients in 326 commands to send replies to all 327 recipients of the replied-to 328 message. The most general 329 consensus, however, seems to be 330 that "Reply-To" only indicates 331 replacement for the "From" field, 332 not for all the recipients. 334 Where group replies to this Followup-To: RFC 1036: 2.2.3, 335 message are to be sent. not standardized 336 for use in e-mail. 338 Address to which notifications Errors-To:, Non-standard, 339 are to be sent and a request to Return- discouraged. 340 get delivery notifications. Receipt-To: 341 Internet standards recommend, 342 however, the use of RCPT TO and 343 Return-Path, not Errors-To, for 344 where notifications are to be 345 sent, and a new standard under 346 development specifies how 347 requests for notifications are 348 specified by a new parameter 349 "NOTIFY" to the "RCPT TO" SMTP 350 command. 352 Whether non-delivery report is Prevent- RFC 1327, not for 353 wanted at delivery error. Default NonDelivery- general usage. 354 is to want such a report. Report: 356 Whether a delivery report is Generate- RFC 1327, not for 357 wanted at successful delivery. Delivery- general usage. 358 Default is not to generate such a Report: 359 report. 361 Indicates whether the content of Content- RFC 1327, not for 362 a message is to be returned with Return general usage. 363 non-delivery notifications. 365 Indicates whether the content of RET in DRPT In forthcoming new 366 a message is to be returned with SMTP exten- Internet standard. 367 non-delivery notifications. sion 368 3.6 Message identification and 369 referral attributes 371 Unique ID of this message. Message-ID: RFC 822: 4.6.1. 373 Unique ID of one body part of the Content-ID: RFC 1521: 6.1. 374 content of a message. 376 Reference to message which this In-Reply-To: RFC 822: 4.6.2. 377 message is a reply to. 379 Reference to other related References: RFC 822: 4.6.3. 380 messages. 382 Reference to previous message Obsoletes: RFC 1327, not for 383 being corrected and replaced. general usage. 385 Used in Usenet News in similar Supersedes: Non-standard. 386 ways to the "Obsoletes" attribute 387 described earlier in this 388 document. 390 3.7 Other textual attributes 392 Search keys for data base Keywords: RFC 822: 4.7.1. 393 retrieval. 395 Title, heading, subject. Subject: RFC 822: 4.7.1. 397 Comments on a message. Comments: RFC 822: 4.7.2. 399 Description of a particular body Content- RFC 1521: 6.2. 400 part of a message. description: 402 Organization to which the sender Organization: RFC 1036: 2.2.8, 403 of this message belongs. not standardized 404 for use in e-mail. 406 See Organization. Organisation: Non-standard. 408 Short text describing a longer Summary: RFC 1036: 2.2.10, 409 message. not standardized 410 for use in e-mail. 412 A text string which identifies Content- RFC 1327, not for 413 the content of a message. identifier: general usage. 415 3.8 Attributes containing dates 416 and times 418 The time when a message was Delivery- RFC 1327, not for 419 delivered to its recipient. Date: general usage. 421 In Internet, the date when a Date: RFC 822: 5.1, 422 message was written, in X.400, RFC 1123: 5.2.14. 423 the time a message was submitted. 425 A suggested expiration date. Can Expires: RFC 1036: 2.2.4, 426 be used both to limit the time of not standardized 427 an article which is not for use in e-mail. 428 meaningful after a certain date, 429 and to extend the storage of 430 important articles. 432 Time at which a message loses its Expiry-Date: RFC 1327, not for 433 validity. general usage. 435 Latest time at which a reply is Reply-By: RFC 1327, not for 436 requested (not demanded). general usage. 438 3.9 Quality information 440 Can be "normal", "urgent" or "non- Priority: RFC 1327, not for 441 urgent" and can influence general usage. 442 transmission speed and delivery. 444 Sometimes used as a priority Precedence: Non-standard, 445 value which can influence controversial, 446 transmission speed and delivery. discouraged. 447 Common values are "bulk" and 448 "first-class". Other uses is to 449 control automatic replies and to 450 control return-of-content 451 facilities, and to stop mailing 452 list loops. 454 Can be high, normal or low and is Importance: RFC 1327, not for 455 only used in the recipient client general usage. 456 (UA). 458 Can be personal, private, company Sensitivity: RFC 1327, not for 459 confidential or absent. general usage. 461 Body parts are missing. Incomplete- RFC 1327, not for 462 Copy: general usage. 464 3.10 Language information 466 Can include a code for the Language: RFC 1327, not for 467 natural language used in a general usage. 468 message, e.g. "en" for English. 470 Can include a code for the Content- RFC 1766, proposed 471 natural language used in a Language: standard. 472 message, e.g. "en" for English. 474 3.11 Size information 476 Inserted by certain mailers to Content- Non-standard, 477 indicate the size in bytes of the length: discouraged. 478 message text. Can cause several 479 robustness and interoperability 480 problems and is not recommended. 482 Size of the message. Lines: RFC 1036: 2.2.12, 483 not standardized 484 for use in e-mail. 486 3.12 Conversion control 488 The body of this message may not Conversion: RFC 1327, not for 489 be converted from one character general usage. 490 set to another. 492 The body of this message may not Conversion- RFC 1327, not for 493 be converted from one character With-Loss: general usage. 494 set to another if information 495 will be lost. 497 3.13 Encoding information 499 Format of content (character set Content-Type: RFC 1049, 500 etc.) Note that the values for RFC 1123: 5.2.13, 501 this field is defined in RFC 1521: 4. 502 different ways in RFC 1049 and in 503 MIME (RFC 1521), look for the 504 "MIME-version" heading field to 505 understand if Content-Type is to 506 be interpreted according to RFC 507 1049 or according to MIME. The 508 MIME definition should be used in 509 generating mail. 511 Coding method used in content. Content- RFC 1521: 5. 512 Transfer- 513 Encoding 515 Coding method used in content. Encoding: RFC 1154, 516 RFC 1505, 517 for limited use. 519 3.14 Resent-attributes 521 When manually forwarding a Resent-Reply- RFC 822: C.3.3. 522 message, attributes referring to To:, 523 the forwarding, not to the Resent-From:, 524 original message. Note: MIME Resent- 525 specifies another way of Sender:, 526 resending messages, using the Resent-From:, 527 "Message" Content-Type. Resent-Date:, 528 Resent-To:, 529 Resent-cc:, 530 Resent-bcc:, 531 Resent- 532 Message-ID: 534 3.15 Miscellaneous 536 Name of file in which a copy of Fcc: Non-standard. 537 this message is stored. 539 Has been automatically forwarded. Auto- RFC 1327, not for 540 Forwarded: general usage. 542 Can be used in Internet mail to Discarded- RFC 1327, not for 543 indicate X.400 extensions which X400-IPMS- general usage. 544 could not be mapped to Internet Extensions: 545 mail format. 547 Can be used in Internet mail to Discarded- RFC 1327, not for 548 indicate X.400 extensions which X400-MTS- general usage. 549 could not be mapped to Internet Extensions: 550 mail format. 552 4. Acknowledgments 554 Harald Tveit Alvestrand, Keith Moore, Nick Smith and several other 555 people have helped me with compiling this list. I alone take 556 responsibility for any errors which may still be in the list. 558 An earlier version of this list has been published as part of [13]. 560 5. References 562 Ref. Author, title IETF status 563 (July 1995) 564 ------ ---------------------------------------------- ----------- 565 [1] J. Postel: "Simple Mail Transfer Protocol", Standard, 566 STD 10, RFC 821, August 1982. Recommended. 568 [2] D. Crocker: "Standard for the format of ARPA Standard, 569 Internet text messages." STD 11, RFC 822, Recommended. 570 August 1982. 572 [3] M.R. Horton, R. Adams: "Standard for Non-standard 573 interchange of USENET messages", RFC 1036, (but still 574 December 1987. widely used). 576 [4] M. Sirbu: "A Content-Type header field for Standard, 577 internet messages", RFC 1049, March 1988. Recommended. 579 [5] R. Braden (editor): "Requirements for Internet Standard, 580 Hosts -- Application and Support", STD-3, RFC Required 581 1123, October 1989. 583 [6] D. Robinson, R. Ullman: "Encoding Header Field Non-standard. 584 for Internet Messages", RFC 1154, April 1990. 586 [7] S. Hardcastle-Kille: "Mapping between Proposed 587 X.400(1988) / ISO 10021 and RFC 822", RFC standard, 588 1327 May 1992. elective. 590 [8] H. Alvestrand & J. Romaguera: "Rules for Proposed 591 Downgrading Messages from X.400/88 to X.400/84 standard, 592 When MIME Content-Types are Present in the elective. 593 Messages", RFC 1496, August 1993. 595 [9] A. Costanzo: "Encoding Header Field for Non-standard. 596 Internet Messages", RFC 1154, April 1990. 598 [10] A. Costanzo, D. Robinson: "Encoding Header Experimental. 599 Field for Internet Messages", RFC 1505, August 600 1993. 602 [11] N. Borenstein & N. Freed: "MIME (Multipurpose Draft 603 Internet Mail Extensions) Part One: Mechanisms Standard, 604 for Specifying and Describing the Format of elective. 605 Internet Message Bodies", RFC 1521, Sept 1993. 607 [12] H. Alvestrand: "Tags for the Identification of Proposed 608 Languages", RFC 1766, February 1995. standard, 609 elective. 611 [13] J. Palme: "Electronic Mail", Artech House Non-standard. 612 publishers, London-Boston January 1995. 614 6. Author's address 616 Jacob Palme Phone: +46-8-16 16 67 617 Stockholm University/KTH Fax: +46-8-783 08 29 618 Electrum 230 E-mail: jpalme@dsv.su.se 619 S-164 40 Kista, Sweden 621 Appendix A: 622 Attributes sorted by Internet RFC document in which they appear. 624 RFC 821 625 ------- 627 DATA 628 MAIL FROM 629 RCPT TO 631 RFC 822 632 ------- 634 Bcc 635 Cc 636 Comments 637 Date 638 From 639 In-Reply-To 640 Keywords 641 Message-ID 642 Received 643 References 644 Reply-To 645 Resent- 646 Resent-bcc 647 Resent-Date 648 Resent-From 649 Resent-From 650 Resent-Message-ID 651 Resent-Reply-To 652 Resent-ToResent-cc 653 Return-Path 654 Sender 655 Sender 656 Subject 657 To 658 RFC 1036 659 -------- 661 Approved 662 Control 663 Distribution 664 Expires 665 Followup-To 666 Lines 667 Newsgroups 668 Organization 669 Path 670 Summary 672 RFC 1049 673 -------- 675 Content-Type 677 RFC 1327 678 -------- 680 Alternate-recipient 681 Auto-Forwarded 682 Autoforwarded 683 Content-identifier 684 Content-Return 685 Conversion 686 Conversion-With-Loss 687 Delivery-Date 688 Discarded-X400-IPMS-Extensions 689 Discarded-X400-MTS-Extensions 690 Disclose-Recipients 691 DL-Expansion-History 692 Expiry-Date 693 Generate-Delivery-Report 694 Importance 695 Incomplete-Copy 696 Language 697 Message-Type Delivery 698 Obsoletes 699 Original-Encoded-Information-Types 700 Prevent-NonDelivery-Report 701 Priority 702 Reply-By 703 Report 704 Sensitivity 706 RFC 1505 707 -------- 709 Encoding 710 RFC 1521 711 -------- 713 Content-description 714 Content-ID 715 Content-Transfer-Encoding 716 Content-Type 717 MIME-Version 719 Not Internet standard 720 --------------------- 722 Apparently-to 723 Content-length 724 Encoding 725 Errors-To 726 Return-Receipt-To 727 Fax 728 Telefax 729 Fcc 730 Mail-System-Version 731 Mailer 732 Organisation 733 Originating-Client 734 Phone 735 Supersedes 736 Appendix B: 737 Alphabetical index 739 Section Heading-field 740 ------- ------------- 742 3.3 Alternate-Recipient 743 3.4 Apparently-To 744 3.4 Approved 745 3.16 Auto-Forwarded 746 3.4 Bcc 747 3.4 Cc 748 3.7 Comments 749 3.7 Content-Description 750 3.6 Content-ID 751 3.7 Content-identifier 752 3.10 Content-Language 753 3.11 Content-Lenght 754 3.5 Content-Return 755 3.13 Content-Transfer-Encoding 756 3.13 Content-Type 757 3.3 Control 758 3.12 Conversion 759 3.12 Conversion-With-Loss 760 3.3 DATA 761 3.8 Date 762 3.8 Delivery-Date 763 3.16 Discarded-X400-IPMS-Extensions 764 3.16 Discarded-X400-MTS-Extensions 765 3.3 Disclose-Recipients 766 3.4 Distribution 767 3.3 DL-Expansion-History-Indication 768 3.13 Encoding 769 3.5 Errors-To 770 3.8 Expires 771 3.4 Fax 772 3.15 Fcc 773 3.5 Followup-To 774 3.4 From 775 3.5 Generate-Delivery-Report 776 3.9 Importance 777 3.6 In-Reply-To 778 3.9 Incomplete-Copy 779 3.7 Keywords 780 3.10 Language 781 3.11 Lines 782 3.2 MAIL FROM 783 3.4 Mail-System-Version 784 3.4 Mailer 785 3.6 Message-ID 786 3.3 Message-Type 787 3.3 MIME-Version 788 3.4 Newsgroups 789 3.6 Obsoletes 790 3.7 Organisation 791 3.7 Organization 792 3.3 Original-encoded-Information-Types 793 3.4 Originating-Client 794 3.3 Path 795 3.4 Phone 796 3.9 Precedence 797 3.5 Prevent-NonDelivery-Report 798 3.9 Priority 799 3.2 RCPT TO 800 3.3 Received 801 3.6 References 802 3.8 Reply-By 803 3.5 Reply-To 804 3.14 Resent- 805 3.5 RET in DRPT SMTP extension 806 3.2 Return-Path 807 3.5 Return-Receipt-To 808 3.4 Sender 809 3.9 Sensitivity 810 3.7 Subject 811 3.7 Summary 812 3.6 Supersedes 813 3.4 Telefax 814 3.4 To