[imp] truncated text attachments?

[Liam Hoekenga]

We're using a SQL based VFS attachment store, and we've received complaints from
help desk that some text attachments are getting truncated.

Our helpdesk has an anti-virus team.  People in the residence halls send this
team reports generated by certain anti-virus utilities.  70% of users using our
central IMAP service use our webmail (IMP) service.  So... they're sending
these reports to the help desk using IMP.  This is the only group of people
that have reported any problems with attachment truncation, and the anti-virus
team think it's a problem with the client, and not the user base.

If it were more widely reported, and hit a less homogenious group of users, I'd
give more creedence to the idea that it's our service... but it isn't.  Any
ideas here?  

Liam