Mail client with SMTP AUTH?

[Nathan Weston <nweston@hamilton.edu>]

Hello,
My school just switched to a new mail server, and without warning began requiring SMTP authentication to send mail off campus. I've been using KMail which doesn't seem to support this.

At the moment I have Sylpheed installed, but it's even uglier than most GTK programs (dons flame suit).

Can anyone suggest a mail client which will do SMTP AUTH?
Here's what I'm looking for:
  Addressbook, including lists... support for kab would be nice, since
   that's where all my data is now. Ideally it would connect to a full-featured, external
   address book, so that I can store phone numbers, email, etc all in one place, rather
   than having separate address data just for my email client.
  Decent filters
  Support multiple accounts
  IMAP would be nice
  A KDE or QT interface would be nice... I would also consider a non-GUI program
   (having heard lots of rave reviews about mutt and gnus)

Thanks,
Nathan