This thread is full of users who don't know what they're talking about.

Blackberry Messenger is NOT AVAILABLE on ANY other platform or devices unless they are built and maintained by RIM. Case closed.

WhatsApp, kik, PingChat are NOT Blackberry Messenger clients. That's it. Stop saying otherwise, because you are WRONG.

If you're confusing BBM with another chat offering, chances are you completely lack the ability to reverse-engineer the protocol and implement it in even the most basic way.