Pet not attacking my target on defensive. Fixable, bug, or just normal?

I don't remember this in Burning Crusade and doesn't happen on Icecrown. Pet on both warlock and mage won't attack my target when on defensive stance. I had to hot key "attack." Is there something I'm missing? Is this a bug? But can't find anyone else talking about it... and just don't know where to post this.

#showtooltip
/petattack
/cast Spell of your choice

Ive been having some issues like this. Even with my pet on offensive it will return to me and start attacking anything else, let alone what I have targeted. I have to manually click attack on it.