Motorola Droid X :: Text Message Sends To Wrong Recipient

My wife has a Droid X which has recently started acting up in the last few weeks. Using the stock Text Messaging app, when she responds to a text message, the receipent name and number is not the person who sent it, but someone else (usually someone she texted with recently). Sending it, it goes to the wrong person. Turning off/on the phone only helps for a short time, as it happens rather quickly again. I have done a Factory Reset on the phone twice and still it happens. I have even gone as far as installing Handcent and she still has the issue, but many times it will show the correct receipent name, but goes to someone else.

The phone is running:

System Version: 4.5.602.MB810