Leaky Sunroof!

I've got this 92 Subaru Legacy and the sunroof has been leaking since day one!  I had someone look at it when I had the seal around the windshield replaced but they couldn't see anything wrong.  I've been trying to locate the drain holes (as I'm figuring they are probably blocked)so I can used compressed air and blow them out, but I can't find the little buggers!

Any help would be greatly appreciated!