SpamAssassin/ProcMail Questions

["Matthew Kelly" <mkelly@cribellum.com>]

I seem to be having trouble getting SpamAssassin running. I have set up Etch
with PostFix, ProcMail, and SpamAssassin. The PostFix setup has been working
fine but I wanted to set up SpamAssassin. So I added the command
mailbox_command = /usr/bin/procmail, then added the procmailrc to the etc
directory. And set up the rules for SpamAssassin. But now all my email ends
up in the /var/mail/ directory but there where going to /home/user/maildir/
Any ideas what I have done wrong?   

TIA 
Matt