Leap attacks fail to do damage

Old: Whenever a spider leaps at it's target, it deals no damage. For some reason, it only deals damage when it's not leaping. This is one of the strangest bugs I've seen and I sure hope this can get fixed soon.

New: So I gave wolves the ability to leap at their targets using behavior.leap_at_target                         And what I expected to happen was:

The wolf leaps at it's target, and does damage when landing on the mob it is targeting.

  What actually happened was:

The wolf leaps at it's target, and fails to damage the mob it is targeting when landing on it.