Vodafone gs2 on O2 Germany

[Goneeuro]

So I may be able to use my girlfriends mothers upgrade to get a gs2 from Vodafone, but I want to use the phone on my O2 account. I know I can unlock the phone easy enough if I root it, but I don't want to deal with some of the issues I keep reading about with rooting this phone. Is there a way to unlock the phone without rooting it. I unlocked my infuse4g from AT&T with one of the paid sites and I don't mind doing that again. I just was curious if I could get an unlock code for free somewhere or somehow before paying one of those sites. Thanks.