box2d version and reference?

[foobarbecue]

Hi, I'm learning IGE and it's fantastic, but I'm finding it difficult to figure out how to use box2D because I can't find appropriate documentation.

Could someone please tell me what version of box2D the stable release of IGE is using? I see it's several years old and missing things like bouyancy.

Additionally, if someone could point me to an API reference, that would be great. Most of the stuff I can find for box2d is for C++ and it's a little confusing to try and translate it.