If that really were the case, how come nobody else has actually bothered in all the years the bounty was up?
Mozilla has certainly evolved since Amizilla had been initiated all those years ago. These changes most likely affected how easy it is to port the software.
One issue with the bounty effort was that the requirements were simply unrealistic and sometimes misguided. As has been mentioned previously, the Firefox user interface is entirely separate from the native OS GUI. This also means it is rather odd to suggest in the bounty requirements that developers should focus on OS3.x and MUI. Obviously, MUI could only be used if you tried to replace the native Firefox UI which sounds like a ton of work for little gain...
