No Service After 3.1.2 Jailbreak on 2G iPhone

[crait]

I've got a 2G iPhone for my mother for Christmas and I'm having trouble getting it working for her. I don't have to be forced into a contract to pay a lot of money a month for something that I shouldn't have to so I wanted to jailbreak it to use it on a Family Plan. I used the latest blackra1n and I called up and told them to disable the internet connectivity for the account but I seem to be missing something because it doesn't get service unless it's in my unlocked iPhone or a different phone.
What am I missing?

By the way, I LOVE THIS SITE! :P I've been lurking around for a while but never really posted. You guys help out sooo much!
So, thanks and thanks for helping again!

[funcritter]

Your iPhone isn't unlocked. Install Bootneuter in Cydia and run it to unlock.

[crait]

Oh, alrighty! Thanks!