Hmmm... sounds like a dns issue....check to make sure that the dns settings (in your tcp/ip properties) are the same on both p.c.'s
You can also try to ping a website by ip address, and if that works, try then pinging it by it's domain name - You can use
www.ibm.com and it's ip is 129.42.19.99
Hope this helps some
/JD
edit - Doh! looks like i am too slow; glad it worked out 
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