XFOR: IRIX Netscape POP3/IMAP4 Client Cannot Submit SMTP Mail

When you use the IRIX(SGI) Netscape Post Office Protocol 3 (POP3) or Internet Mail Access Protocol 4 (IMAP4) client to submit a Simple Mail Transfer Protocol (SMTP) message to an Exchange Server computer, the message may be rejected or not leave the Outbox. This problem occurs only if one of the following client restrictions is enabled on the Connections tab of Internet Mail Server properties:

�	Clients can only submit if homed on this server
�	Clients can only submit if authentication account matches the SMTP submission address

Although the authenticated connections are accepted from the same client, and retrieval of messages through POP3 or IMAP4 may work, the application log of the Event Viewer may show the following error message:

   Event ID: 4151
   Source:  MSExchnageIMC
   Category:  SMTP Interface Events
   Description:
   An inbound mail message was not accepted on <Exch.MyDomain.com>
   because the authentication account did not have permission to use the
   originator address on the message.
				

The problem occurs because the Netscape client adds the RFC-822 header "SENDER", populated by the user's logon name from the foreign system. This does not match the authentication account, which was in the format: Ntdomain\Ntaccount, and Exchange Server rejects the submission. This occurs if either or both of the above client restrictions are enabled.

To resolve this problem, edit the Preferences.js file located in the hidden directory ".netscape", in the user's home directory on the IRIX workstation. This is a Netscape preferences file that instructs the Netscape client whether to send the SENDER header information. Editing this file can suppress sending this header information.

To edit this file, perform the following steps:

1.	Open the Preferences.js file using a plain text editor, and verify that the following entry exists: Pref("mail.suppress_sender_header", true);
2.	If the entry is set to "false", edit the entry so that it appears as in step 1 above.

If you are not able to edit this file, there is an alternate workaround. (NOTE: This workaround retains the client restrictions for all hosts except those specified in the workaround):

1.	In Microsoft Exchange Administrator, view the Internet Mail Service properties.
2.	Click the Connections tab, Click Accept connections, and then click Hosts.
3.	Click Add, and type the IP address and subnet mask of the IRIX host using Netscape. If you want authentication, specify it here.
4.	Select the "This host is a relay server" check box.
5.	Stop and start the Internet Mail Service.

This workaround must be performed for each IRIX host that will be submitting SMTP mail to the Exchange Server computer with the Netscape Communicator client.

Note that setting the IRIX host as a relay server will override the security settings in the Connections property sheet.

The SMTP protocol log shows successful authentication by the Exchange Server computer and proceeds through "354 Send data", at which point the Exchange Server computer will issue the following message: The session then terminates without accepting the message.

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