Unfortunately, there is little documentation. I have looked into adding this for my extensions, and didn't manage to do it. Same documentation issues I had when I first started to port my extensions for Firefox to Fennec: pieces of documentations here and there, but nothing that clearly explains the differences between the 2 platforms.
That said, their extension framework is by far the most powerful of all browsers.
https://developer.mozilla.org/en/Extensions/Bootstrapped_ext...