Make sure you have NOOP turned off. Also if you do a netstat from the command prompt you will notice that the ports in use are in TIME_WAIT. I have been using the same config since I was using Win2000 server and it hasn't been getting stuck in TIME_WAIT until SP1 was released with the new TCP/IP changes.
Details of these changes can be found here.
http://www.microsoft.com/technet/com...1204.mspx#EBAA