How does Caster Agro Work if Line of Site.

I like to tank but server i'm currently playing; if next pull I aggro has casters and I line of site them they will stay where they are until oom, then run to the pillar im hiding behind. Very annoying!. From what I remember from live if I did this, the casters would move until they had line of site on me then start casting away.
Hows it work here ? and as a side note am I remembering it wrong on live cuz I swear I remember los'in everything on my pally and beating everything down in a nice little bunch.

It works correctly here... most of the time.

Hi, u are right in some instances LOS pulls just dont work.
For example SHH is a **** show not a single ranged mob will walk towards u when u los them.
There are some pulls in bota that do not work either.
In SL it seems to work tho, kinda wierd that 1 instance does work and the other does not.
Would be sick if this can be fixed @admins.