IMAP/POP3 servers and disk quota problems

Hello,
I'm having some problems getting UW-IMAP and Qpopper working with disk
quotas. It seems both UW-IMAP and Qpopper want to place .lock files
in the spool directory, which is causing problems because the users
cannot POP the account or delete messages with IMAP if their quotas
are maxed (the .lock/temp files cannot be created). The system I'm
using is running Red Hat 7.1, with the usual sendmail/procmail setup.
Procmail makes it easy to specify another location for the .lock files
(besides the spool folder), but I have not been able to find any
documentation that says UW-IMAP and Qpopper can do this. Basically
I'm looking for a way to get procmail, the POP3 server, and the IMAP
server to all use the same .lock/temp files, in a location other than
the spool directory, so they will not affect disk quotas. I have also
tried having procmail put mail in ~/mbox instead of /var/spool/mail,
but it appears that both UW-IMAP and Qpopper put the .lock files in
the same folder as the mbox file, which causes the same problem with
quotas.

Does anybody know if UW-IMAP and/or Qpopper will allow the .lock files
to be specified, other than the default location with the mail spool??
I'm also open to any suggestions on other IMAP/POP3 servers that do
work well with disk quotas.

Thanks for all feedback...
--
Chris