I use GUIMiner (2011-07-01 version) with poclbm kernel.
Two of my workers connect to the internet directly from the first computer, and two another connects via shared internet connection from another computer (I don't have a router, but have 2 LAN in my first computer). Perhaps, problem in it? Can you tell me the numbers (or labels) of my workers with no longpolling?
That is awfully coincidental that you have your computers are split up two and two, and I'm only seeing two with an LP connection.
Right now, the way the logs are written out, all I see is how many LP connections per user, not per miner. I will need to jump into things to get that on a per miner basis, give me a little bit to get that info for you.