Improved Hunters MarkFollow

I have improved Hunters Mark but I'm not sure that it's working for melee damage. When I flag it on a mob it only says it is increasing ranged attack power. Is this normal or is there an issue? Thanks!

It works, the best way to tell is to place your pet on the mob first, watch the damage closely and just make a mental note of how much he hits for everytime. Then apply your hunter's Mark and you'll see it go up just a bit. Tooltips rarely display the added bonus of talents.