You set a pull spell? And a reasonable auto-hunt range?
You clicked set a couple of extra times after typing your pull spell (case sensative)?
You have a parsable target solution in your selection of mobs to pull, ie, your not ignoring grey, green, blue, white, orange and red? Or your surrounded by white+ and your ignoring white+?
Beserker works fine, used it yesterday even. My guess would be a pull spell not set properly, or the parameters around target selection don't provide a positive target within the auto-hunt range you are using.
$0.02