Its obvious there are going to be teething problems until the first update of OS X 10.5. If its that much of a problem, I'd recommend reinstalling Tiger until the problems are rectified, there is nothing you can do really.
I'm not using it, but from what I can see it's not really time-critical anyway, is it? They'll surely adapt it to the changes in Leopard eventually.
From what you're writing it seems the authentication doesn't work properly. Maybe you just need to reinstall AppleJack, but I would be cautious - system-level tools should only be used on system versions which they've been explicitly tested on!