URL change, map

Hi,

I would like to add www in url when user(s) do not add www with domain name. E.g. if users type Example.com, my site should make this url to www.example.com. Is there any web.config configuration available? or any code that I could use? I am using VS2008, Framework 3.5, and IIS 6.0.

 Thanks in advance. 
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