How do I delete user names from the drop down?   

When signing in to MSN there is an username field, and a password field. The 
username field has a drop down list of other users who have signed in to 
their msn accounts using my Mac. Is there a way that I can clear the drop 
down list history/ cache so no other usernames appear?

Thanks

date: Wed, 20 Feb 2008 16:10:06 -0800   author:   Arthur