iPhone 4S Messaging - U instead of Enter?

I bought the iPhone 4S from Cricket Mobile on Friday. Transfered my account data from Virgin. Whenever I recieve text messages, when the person texting me types the enter or return key in a text, it instead shows up as a "U".

So, if the person types:

"Sentence 1.

Sentence 2."

It comes through as:

"Sentence 1.USentence 2."

I exchanged the phone today, same issue. I got a new phone number, same issue. Nobody at three different Cricket stores, Best Buy, Cricket Tech Support, or Apple Tech have ever heard of anything like this. Could it be that sometime when my account information was transfered inbetween networks, something went wrong? What should I do? Should I get a brand new Cricket account, that way I can start fresh? I'm really getting frustrated. Thanks in advance!