Dustin and Misterre, it might help if you posted what brand/model router you're connecting to. Be interesting if both were the same. It's obviously not the phone and 2.2 alone, because most people aren't having the problem.
It seems to me that when they sleep, your phones aren't disconnecting, at least not so the network knows about it, so when you wake up the phones and they try to log on, the network tells them they're already on. It's certainly possible that code changed somehow between 2.1 and 2.2 that made this happen.
Once the phone sleeps, you might also try going into your router settings and seeing if the phone is still listed as active on the network. Mine is listed as inactive when it's sleeping and active when it wakes up. It stays active for a while after it goes to sleep.