We just recently updated our Exchange 2007 Standard hub transport server to Update Rollup 6 (for SP1) and are noticing different behavior. When our VMS system sends a message to Exchange via SMTP containing CRLF+NULL+CRLF in the message body, Exchange accepts the entire message fine but the recipient only sees the message body up until the first CRLF+NULL+CRLF. This was not a problem before the update. Can anyone else verify this same behavior? In case it matters, this is on a receive connector with no authentication and allows anonymous users.

After more testing I discovered that it truncates everything after the first null character in the message body. It doesn't matter where that null character appears.