Which animation software is this?

[Dr.Biotox]

I really want to know which software is used in Avatar animation, and I can see it in this video, but I am not familiar with interface of it, so if anybody can recognize it, I would really appreciated.

Thanks

Here's the link http://www.youtube.com/watch?v=1wK1Ixr-UmM&feature=related (1:26)

[brettSinclair]

motion builder.

[Dr.Biotox]

Thank you very much :)