Mail shows empty message body
I have Mail setup for both my home account (gmail/IMAP) and my work account (Exchange). Sometimes my work Inbox will list a new mail message that says under it "This message has no content") and, sure enough, when I click on it, it'll show the header (from/subject/etc) but no body.
The problem is: everybody else in my group *does* have a body to their email. None of the other users are Mac Mail users - most of them use Microsoft Outlook (one uses Thunderbird with IMAP).
Is this some known bug in Mail? Is it just a poor implementation of whatever proprietary protocol MS Exchange uses? In other words, if I switched over to using IMAP, will this problem go away?
[Ancilarily, I also sometimes don't see attachments that everybody else in the group sees :-(
Any info/help is much appreciated.
P.S. I'm on a MacBook Pro running Lion 10.7.2 - all the latest updates.