Plus if it's simply a case of redirecting, there's no need for virtual hosts - these are when you want to run multiple, separate websites (domains) off one single IP.
This is what I am trying to achieve. I have .com as my main site, and i want it when people go to .co.uk it changes to.com. I am running off the Heart Internet servers.
If so, go to the domain management section of your control panel, and you should be able to set-up a redirect there. Otherwise, submit a support ticket explaining your requirements and one of the staff should set it up on your behalf