Unless you've applied a lot of patches, Qmail really isn't a very good
server. Most significantly, it doesn't check the recipients of messages
before accepting them. I used to run Qmail, and it was a major hassle.
So apply all the patches and u will have a very good server.
Patch it with chkuser and it will check for local vpopmail users, envelope
syntax.
I recommend Courier to Qmail users, since you'll find it very similar. It
has a considerably better feature set, to boot.
(http://www.courier-mta.org)
I use courier only for imap. best imap server around.
