I'm very surprised by the interest about the 500D port of Magic Lantern, that's great: congratulations to Alins, Chuchin, Coutts and others developers! I generated the stubs before 550D release and it also indirectly helped to find 2010's keys.
Provided that I'll have no time to maintain 50D code (and do not own this camera), I can eventually at least generated 50D stubs and consts files.
Is there any interest about it ? I'll initial provide support to any developer.
Of course 600D/T3i and 1100D/T3 are my top priority, but they are not yet available.