have a copy of class-dump to get the symbols/methods/vars ichat's classes use..
then you're good to go.
InputManagers are so useful, without them my next app would not exist!
BUT keep in mind that you're patching something that could change anytime... it's still an ugly hack.. always remember that!
for instance, in my hack, I have 3 lines of code, so it cannot reall cause any troubles. but if you're going to redraw stuff, you better be careful!