Nokia :: E75 - Cannot Reply - Cannot Send Messages

I can receive email but I cannot reply to it since I cannot send out messages. I have reported this over the phone to a Nokia Hotline but no solution has been found. In one of my trips to Manila I went to a Nokia Care Center in SM MOA and they also said nothing is wrong with my phone ,they claim that with their own sim card they can send and receive messages . So Again I went Smart Iloilo Philippines where they also told me nothing is wrong with the with the operator settings.

I really don't know where to turn to; I got this E75 because I need the push email services badly. My user name in the Nokia messaging is and my Cel phone number is. Is this a software or hardware problem and has anybody encountered a similar problem