Level placeholder in the name of a disguised mob does not work

Hello there!

I am trying to make a zombie that can climb walls, (a spider disguised as a zombie)
that has custom levels,

i already made a random level maker for the mob, but i can't get the name running, it says Always 0.. (<mob.level>)

but the mob sends a message when killed, and than it does use the right level...

any suggestions?
thanks
AnimalMace