Totally wrong in the rulebook mate, and that is where the problem lies, a penalty for handball is to given for intentional handball, thats what your taught as a ref but it just doesn't work that way when a games in flow.
That handball rule really should be about natural position (ie, if hands aren't at side or in front of the torso it's not a handball). Seems odd that an inadvertent mistimed tackle is a foul, but not with handballs.