getting stuck on stairs/steps

my arena mate (female undead) is getting often getting stuck on stairs/steps, witch is especially frustrating in the lordearon arena, at the tombstione in the middle. But can also be a problem many other places, also beside arenas.
I asked in my guild and many have same problem. One from my guild said its the server witch has very bad terrain or something.
I myself (male undead) almost dont have the problem at all, witch i find weird. Is this something specific races or genders have more trouble with than others??, and what can we do to fix it or make it better?

It happens a lot, specially on the stairs going to kara's back entrance, it was like that on retail too.