[imp] IMAP messages not displaying in IMP

[Eli]

I've got a weird problem where a particular user has an INBOX with a few
thousand messages.  IMP is able to see the count of messages in the INBOX,
but whenever the INBOX is selected, it takes a while and then IMP returns
that there are no messages in the folder.

I have seen other cases like this before and it was due to a very large UID
number on the messages (the UID in these cases is part of the message
filename, so I am able to rename them to change the UID to something lower).
I have done this (renaming files) in the past to fix this problem of
messages not displaying, however in this particular case the UIDs (according
to the filenames) is not very large at all, so I cannot figure out why the
messages aren't being displayed.

I don't mind trying to troubleshoot this myself, but I don't know where I
should start looking (I'm assuming somewhere in horde/lib/Horde/IMAP/...).
Help?

Eli.