Look at his signature in the Cinderella drawing here: http://twitpic.com/2mf6n3 (via @MJJPhotos). Same one!

Honestly it looks like the J he signs with.. and Mjs writing if you analyse it is full of caps and joined as well as single letters

Hmm.. Doesnt really look like his signature overall but I see the "l" and "J" and are quite similar to his signature in later years.. Perhaps like what you said, it was drew in '70s,therefore the signature was a bit different.

And why glasses at the boy if is him?

I think I read somewhere that apparently Michael drew this in the early 70's so it could explain the signature.

doesnt look like his signature but the pants on the boy look like the pants on the NO war artwork he did

hmmm.....maybe where did u get this at