AntiSpam leaves undelivered mail on server

I use (verizon dsl ) email. My email client is Outlook 2003. AntiSpam does a great job of filtering and preventing this ■■■■ from appearing in my in box. However any mail that goes to the quarantine database stays on the server. I have Outlook configured to download mail from server and to not leave a copy on server. Eventually, this will fill my online mailbox and prevent me from receiving new mail. I can delete it every few days manually by going to the email server via the web browser… but it seems there should be a better way to accomplish this instead of manually removing it.

Anyone have any ideas?