XCON: Linear Whitespaces Replaced by Single Whitespace When Unfolding MIME Headers

ID: Q176045

The information in this article applies to:

Microsoft Exchange Server, version 4.0

SYMPTOMS

The Microsoft Exchange Server Internet Mail Connector (IMC) might fail to convert an incoming internet mail message. The IMC will not correctly parse MIME headers that wrap across lines. The problem appears with MIME Content- Type headers where the boundary is broken into two lines.

CAUSE

When the IMC unwraps these headers, it removes all spaces. Although this conforms to the RFC, this creates a message with an invalid message header and thus the message cannot be processed.

For example, if the IMC receives a header similar to the following, it won't be able to decode MIME attachments:


  Content-Type: multipart/mixed; boundary="----
                 =_NextPart_000_01BC87E8.4103ECF0"

This header happens to have been generated by the IMC and comes back to an IMC that does not understand it. In this case, there was a Soft-Switch LMS 2.0 between the IMCs.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange Server, version 4.0. This problem has been corrected in the latest U.S. Service Pack for Microsoft Exchange Server version 4.0. For information on obtaining the Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

MORE INFORMATION

For more information about this problem in Microsoft Exchange Server, version 5.0, please see the following article in the Microsoft Knowledge Base:

Q175236 XFOR: Failed Message Conversion Error on Inbound Messages

Keywords : kbbug4.00 XCON
Version : 4.0
Platform : winnt
Issue type : kbbug