Excuse my retahded air conditioning terms, but how *hard* does your AC blow? If you don't feel the air ~5-6 feet away from the AC, then the air probably isn't circulating. What i did to fix our AC problem at my house (my living room is medium sized, and the AC would only project the air ~4 feet), was to setup a fan DIRECTLY in front of the AC. In doing so, the fan would pull the cold air, and direct it across the room. Hopefully the cool air will ricochet around the walls of your room, therefore cooling zee hot room of yours.
BTW, this only applies to those ACs that stick outta the window 😛