Outlook 2003 with pop account rules don’t work

I have Outlook 2003 at my work. I have a pretty complex rule structure set up to sort the hundreds of emails I get a day. I also have a personal gmail account. I added it as a pop3 account in outlook, so I could get my personal messages as well. I set up a rule to sort all my gmail messages into a specific folder. BUT, now none of the other rules I have work (just the gmail rule). If I delete the gmail rule, then my previous rule set starts working again. Does anyone have any ideal why this might be happening?