Hi,

>
> Any other ideas?
>
>> Are you sure this is not a Windows license limitation?
>>

BTW, have you look at Windows Events?? It may tell you what's happening.
I've found this doc that may be related to your problem:

http://www.mydigitallife.info/2005/11/15/windows-xp-sp2-tcp-connection-limit-event-id-4226/


Regards,
Anderson Farias