I use spamcop to scrub my mail and for its IMAP function. With the upgrade to BIS 2.0 blackberry now is able to integrate with IMAP accounts.
However, some actions muse be taken on the back end for sync with Sent Items folders and instant push email.
I have included the link from RIM's website which explains the upgrades.
However, it does not say what the email admin must do to make said changes, if you(the admins) are either unable or do not have the time, I would be happy to make the phone calls and give you the info.
If it would be at all possible to make said changes I would appreciate it.