New iphone 4 owner needs help

[tempest]

Hi - I am new to this forum so merry christmas all!! Anyway I have opened my new iphone 4 this morning and all is well but I can't get the mobile data network up and running? the phone was purchased from vodafone and is pay as you go, someone said somthing about " it thinks its a contract phone and need something changing on the set up" but I don't know how to. If you could please help I would be most grateful.

 

[IPAD_IPHONE]

Merry christmas....