I can even write scripts for whiptail for receiving and sending SMS and storing the data and the same for calls, IF ofono works and you can indeed access its API...

Used those for a year on HTC Universal, which had pure Debian running, without Ofono, but it had a whiptail frontend for calling and SMSing and worked well.

I just need to know if the N900's modem is working, and you can send and recieve and SMS, and make and receive a call...

I think the SMS functionality has been confirmed as working before, so that would not be a prob, the phonecall part is what's more important though...

The whiptail scripts would be just the base, I'm sure if the basic phone functionality is working, you'd have a proper Qt frontend programmed by someone soon...