I'm having a problem with the jumpthru behavior while trying to create a doodle jump clone. If the platforms are to close to each other, I get a very strange behavior. For example the sprite stops jumping, falls through platforms or gets stuck.
You can look at my sample here: http://dl.dropbox.com/u/1159473/testjump.capx
I think the problem reported by kirby is similar or even the same.
Is there any solution/bugfix for this problem?