Quotes not expiring

Hi everyone. I'm baffled. We have some quotes that should have been marked as expired back on the 19th on January. The quote was marked quoted on 12/20/10. Our quotes are set to have an expiration date 30 days after the quote it is marked quoted. I just can't figure out a rhyme or reason for why these quotes are no longer switching to expired automatically even though the expiration date as passed. We are on 9.05.602A. Thank you in advance!

Emily