i left the cookie setting the way there were in SMF and i didn't see any cookie prefix in it's setup. i did not see any cookie setup in photopost installation either other than when it asks if there is a prefix for the cookies. when i log in, it says login was succesful!
urls are
www.digitalpick.com/dpforum (for SMF)
www.digitalpick.com/dpgallery (for photopost)