xp network issues

Greetings all,

We have a fairly small shop of about 70 pc's and 4 locations, we run off a windows server 2003 and exchange 2003 with several other servers for various things. As my first order of business here i pushed out xp to all pc's that were on 2000, all of them, and then this year in feb i rolled out WSUS. I have had several network issues, symptoms being users locking up "freezing" like there network traffic has just stopped. I am at a loss as to the cause, I put a p4 in one of the pc's that had a Celeron thinking that maybe an issue,

OK enough history, i have heard on a news group i belong to that there was a Microsoft security patch that seems to be causing this but they said MS was trying to narrow down the patch, have any of you MS guys heard of this, my users want to kill me......

 

Maybe something to do with this??