T-Mobile charging for incoming SMSes

Today I just found out that T-Mobile in the US wants to charge their prepaid customers for the incoming SMSes. This seems totally outrageous, and one of the reasons I decided to chose T-Mobile was the free incoming SMS option.
I tried to contact them and send them the following e-mail, but unfortunately you can not contact them unless you give them the last 4 numbers of your SSN, and since they don't have my SSN, I don't see how this would help them validate my identity.

So since I was unable to send it to them, I'll post it here, as some sort of "Open Letter". Not that I expect they will read it, but why not?

Hi
I just wanted to let you know that I am very dissapointed at the "pay 5 cents per incoming SMS" idea.
From now on, I will not use the SMS service again, and as soon as another GSM operator will come in my area (Besides for Cingular/AT&T) I will switch away.
I don't find this kind of changes acceptable.
It's not about the money, it's about trying to steal from the customers.

With more and more free WiFi hotspots, you guys will soon have to realize that your services are becoming obsolete, and you should treat your customers better if you expect to keep them.