I was having a bunch of problems with dropping the connection, especially on wake. I tried all the solutions posted above with my MBP, bought a new wrt54gl, etc, was still having the problems. Recently I moved from my apartment in a big building to a normal house in a neighborhood and the problems are gone.
The difference before was that there were easily 10-20 wireless networks present, and now there are only my own network and 1 other that my mbp sees, which leads me to think wireless crowding might be a problem.
The difference before was that there were easily 10-20 wireless networks present, and now there are only my own network and 1 other that my mbp sees, which leads me to think wireless crowding might be a problem.