buddypress and using www's in the domain name of the main site of a MU site

Right now, I am not able to add www to the domain name and keep buddypress working - all the http://www.domain.com/anything is redirected to the main homepage - domain.com. it is NOT redirecting to the actual page (domain.com/anything). any ideas on how to get each page to redirect back to the page it reresents without the www's?