VPN connection issue

Good morning IT people!

Based on link:
http://articles.techrepublic.com.com/5100-10878_11-1056227.html

I have setup a VPN server (windows XP Pro) at home. In office, I can connect my home VPN without any problem. However, once I get connected, my work PC’s internet connection (like office outlook, Yahoo messenger, MSN) all get broken, and wouldn’t be accessed any more.
Would anyone please help me out?
Many thanks!
can2000@