Apparently, there are more wanting to use their tablets to make calls and send text messages. An iPad 3G has been turned into an iPhone by a team called iPhoneIslam, allowing the iPad 3G to make voice calls, send text messages and use FaceTime.
There is an app available from the team, called the PhoneItiPad which turns the iPad 3G into an iPhone. You’ll need to get your iPad jailbroken and download the said app from Cydia.
Once the PhoneItiPad app installed on your iPad 3G, you’ll be able to make calls, send text messages and use FaceTime on the iPad. Of course, you must use a microSIM card that’s associated with a plan allowing for making and receiving calls instead of for data only. A clip is included below showing how it works.