Yes. I'd expect Neo900 is of the few devices that are not vulnerable to this kind of attack at all. The worst bunch is anything with integrated SOC running baseband having shared memory access with main CPU. However, I personally feel that it is significantly higher risk to get your device infected with "standard" malicious SW having nothing to do with BB or 3G stack. There exist loads of crap especially for Androids aiming for that. True, there currently being no device that does detect it (as I believe cryptophone is still vaporware...)