I am trying to delete POP3 spam on my POP3 mail server.  I have created and saved the tools-mail filtering rules-create /edit POP3 rule set using words repeatedly used in the spam headers, then I have edited internet mail options-receiving (POP3)-edit- download controls and selected the relevant rule set, then OK'ed or saved everything and re-started PMAIL.  However, the rule does not delete the spam on the server as expected.  I am using the POP3 toolbar, and neither selective or general download buttons achive deletion of the spam - the messages remain available for download, and are not deleted under any option.  Am I missing a step, or are some ISP servers not able to accept such instructions, or any other possibilities ?