Batch Change Address Book Contacts' Area Code

[rainmanbk]

A friend of mine just purchased an iPhone and is having a problem with SMS. He told me that on his old Treo, the area code was a default setting and the phone book numbers didn't need the area code included it in. So all 400+ of his contacts don't have area codes, and he would simply use a different one if the default wasn't right. So anyways, the problem is that his iPhone isn't use a default area code. So he can't send SMS messages to anyone on the phone whose contact doesn't have an area code. Obviously you can see why he is upset about this.

Is there anyway to write a script or somehow batch change the area code of address book entries in group x, or something of that sort? If anyone can help, I'd appreciate it!

Thanks!