James Cameron helped out in that film since it was made by his ex-wife whom they share their projects with from time to time; in an Obi-Wan kind of perspective they both win

He seems like a good guy, he hopes she gets acclaim to help her career, goes to Iraq to boost morale (his bro was a Marine as well; and no the guys in Avatar are not real military - fething mercs

), etc.
Likewise she helped out with Avatar. Hollywood sure is a small world.