I had unlocked my Captivate from AT&T to use it with vodafone (Germany) without any problem - can receive and make calls and have access to the internet with 3G.
When i check my network state i had an screen with empty fields of MNC and so on - does it must fill in with the local code for vodafone?
As far as I know, that information is based on the phone's CSC file.
It shouldn't be a problem.