To do this here is a little tutorial to guide you there 2 methods, I suggest the easiest (note it seems that in some cases, not mine in any case, the notification SMS from unknown then put you the contact in your book, but once in the SMS you have of course the name of the sender):
Acknowledgment iPhone SMS
* Launch Cydia
* Once in Cydia -> Manage -> Source, add and install the source http://iphonedelivery.advinux.com/cydia
* In Search -> find the application iPhoneDelivery
* Install the application
* Your system restarts, wait
* In Settings -> Messages, select Acknowledgment and Flash AR (this is the info bubble that gives you the details)
After several tests, everything works perfect, no problem!
In addition it does not make you an SMS acknowledgment but just a warning.
(extracted from nightgamer)