If you look at Google's cached page, it looks like they fetched http://qdb.taranen.co.uk/ at 2009-11-06 07:47:43 and your page came back.

When did you acquire your current IP address? If it was some time around that point, my guess is that they had your IP address before you did, and thir DNS (or google's cache of it) was out of date.

I am not sure what to do or how to resolve this.

I don't think there's anything you can do aside from waiting for Google to re-crawl. For future reference, though, this is a good reason to only serve up your site in response to HTTP queries which come with the right Host: header.