Is my case similar to yours?
I've been running into a case I think might be related to this issue. Win7 SP1 x64 machines joined to a domain, get their IPs through a Cisco helper. On system wake (seen it from sleep, not sure from full boot) have intermittent issues with "no log on servers" error. NIC shows it has a connection, but if I log in with a local account Windows tries to get an IP then gives up and actually tells me the network connection is unplugged. Reboot generally solves the problem.
I went through the directions in the MSKB article and on my systems at least, the TCP-IP interface already had the force broadcast flag set to 1. I've tried different drivers and autonegotiation settings without luck. Trying now to disable the public-profile firewall in case that's the isuse.
Any word on when Microsoft might make this hotfix available so I can test that? Trying to track down these issues in two computer labs is driving me crazy.