Quote from Orkie:

Senor Quack has discovered that GPH released the complete 4.1 source code on the sly. They didn’t tell anybody! The menu code is even available now. I don’t know if they intended for that, they’ve always been pretty anti releasing it before, but now we have it regardless.

Sources: http://dev.gp2x.com/files/sources/

http://www.gp32x.com/board/index.php?showtopic=43043&view=findpost&p=626458