Hi Alessandro:
It's great to have that porting. I have taken the liberty to use your bridge for some demos and it runs smooth, so it's great to have an "official" implementation, I'll use it if you don't mind. I've found no problems using the Bluevia SIM, as it is pure outgoing TCP/IP traffic.
Have you thought of changing the library so it runs with any kind of client class? Or do you want me to take a try?
Best regards.