Thanks Chrysalis, i did have a look online and there's conflicting information. Hopefully it won't be too difficult to get them to send me an unlock code.
---------- Post added at 23:51 ---------- Previous post was at 23:35 ----------
This site says that VM payg phones are locked but pay monthly aren't !
http://www.uswitch.com/mobiles/guide...mobile-phones/
I guess I could just try a different sim and see what happens.