Spam Filtering

The company I work for spam filters my mail. This would be a good idea except it never filters out spam instead it filters out mail sent internally. Doh! There I was thinking spam filtering was meant to simplify reading mail, instead every day I have to open a message in order to go to a web page to release work mail. For comparison my work address gets around 2 spam mails a week (these are never caught) and my gmail address gets around 60 a day, with virtually zero false positives and a couple of false negatives a day.