Mail interface: Unread mails and server-side filtering?

I'm making a web-based email system using imap. This is part of the feature set I'm planning on implementing: 1) Multiple folder support. 2) When viewing a folder, unread mails should be marked as such. 3) Server-side filtering into different folders using procmail. But I can't figure out how do combine these requirements. The mail server can tell me which mails are unread because those mails are still in /var/spool/mail. But I want to filter incoming mail on arrival using procmail into various files under my ~/incoming-mail directory. That means the mail server can no longer tell which mails are read and which aren't. If I make my mail interface keep track of which mails are read and which are unread on its own, then it won't be compatible with other mail programs. Then if I start another mail program, it will think all mails are read, even if they aren't. Am I going to have to drop procmail, and put my mail-sorting filters into my mail interface instead? Any help appreciated. ===== -- Christer Enfors _______________________________ Do you Yahoo!? Declare Yourself - Register online to vote today! http://vote.yahoo.com