htaccess - using www and non-www together

Hi,
I have a site (http://sub.domain.com/) that's working fine. Now what I am trying to achieve is that http://www.sub.domain.com/ should also work. So irrespective of whether user types in http://sub.domain.com/ OR http://www.sub.domain.com/, both should work. Please help

Cheers :)

I thank all of you (30 viewers) for taking time to view this post. I figured it myself.

Cheers :)

Well, this isn't really the most active forum and I shall admit that I have browsed this topic several times before :p But could you please be so friendly and post your solution so the later generations can go to this topic if they encounter the same problem?