Setting up domain mapping

Hi,

Can someone explain how I can map a domain to a wordpress blog in multisite that's setup with user blogs having a file extention and not a subdomain?

I have a test blog that I setup at http://stickytrade.com/webezy/

I am using a spare domain name called bestbuyfeed.com for which I added DNS "A" record pointing at the IP address of my server: 74.124.217.32

I have placed the domain mapping plugin in the correct files as required. I have also setup my dedicated ip to point to my website sign up page.

However when I add the domain bestbuyfeed.com to the domain mapper nothing happens. Have I missed something?