Could anyone advise me as to what might be going wrong here? Your help is
Go through /var/qmail/users/assign and update the user and group of every entry to match the new user/group for vpopmail. Run qmail-newu so it rebuilds the users/cdb file.
Go into your vpopmail source directory and rebuild vpopmail. It would be best to make clean and re-run configure with the same options as you previously did. In a pinch, you can edit VPOPMAILUID and VPOPMAILGID in config.h and just re-compile. Install vpopmail, and rebuild qmailadmin as well (so it links the new vpopmail libraries).
You said you were using binc-imap, so you won't need to recompile it. If you were using Courier-IMAP, you'd have to recompile it as well (since it links libvpopmail).
That should cover it!
-- Tom Collins - [EMAIL PROTECTED] QmailAdmin: http://qmailadmin.sf.net/ Vpopmail: http://vpopmail.sf.net/ Info on the Sniffter hand-held Network Tester: http://sniffter.com/