Trying to get females interested in comp sci at the university level is a mistake - it's too late. Most people already have an idea of what they want to do by then and if they know nothing about computers it's a little intimidating to jump in like that.
I think the numbers will eventually go up on their own, since kids of both genders are using computers from an early age now and it won't be such a big leap. I liked computers as a kid, but I never really got into them until I was older because none of my friends (girls) liked them, too. I think I went to one computer club meeting in high school, but I stopped going because some of the creepy guys there kept asking me out. It wasn't that I wasn't interested, but there were other things I was also interested in that were more fun socially.