IPhone :: App For SMS Backup To Gmail?

So after searching the forums and Google and iTunes and just about everywhere I can think of, I still can't seem to find the app I need.I just bought my iPhone 3G-S yesterday, after using android for almost a year, and the ONLY one app/function i can't seem to find is for my SMS to be backed up automatically to an e-mail account.

On android there's an app called SMSBackup, in which all you need to do is enter your google username and password, and then it backs up all your SMS automatically to your Gmail address as soon as you receive them. They appear under a label and are archived automatically, and when you go into that label you see them as threaded conversations. I can post screenshots if anyone would like me to.

I'm surprised that with the number of apps for the iPhone there isn't a single app that does this? At least from what I can see.

Does anybody know if there is actually an app that I've overlooked and that does what I'm looking for? Or if there's an app that is in development to do this? The android one is open source so I'm sure it can be done on the iPhone, no? And before I get flamed for this, I do know they are completely different operating systems and are developed differently.

Is it because of the one-app-running-at-a-time thing? Because surely that shouldn't stop it with the new app (i forgot it's name) that allows you to run multiple apps in the background