[imp] Moving a message in IMP gives a "You exceeded your mail quota" error

[Ryan Flannery]

Hello,
under the following setup,
   Horde 3.0.4
   IMP 4.0.3
   Courier-IMAP 3.0.5
   vpopmail 5.4.10
   OpenBSD 3.7

Whenever the Administrative user (the one listed in the Horde
setup "Authentication" tab) tries to move/copy a message from one
folder to another folder, the following error is had:
   "There was an error moving messages from "INBOX" to "test".
    This is what the server siad: [Alter] YOu exceeded your
    mail quota."

But the user is no-where near the quota limit.
For non-administrative users, everything works just fine...weird.

I've created a dummy account for administrative purposes, so it's
no big deal....just odd.  Anyone else experience this?

Also, I've checked the permissions on the IMAP directories and
they're OK.  I've even removed the user and started from scratch
(countless times) and that didn't help.

-Ryan