Help the game is unplayable!

Hello
I have faced a problem that made the game unplayable- some characters i create have "lags" and by "lags" i mean they tp instantly to the location i've been at a few seconds before. It looks like a lag but i've checked my internet few times and everything was running smoothly. It happens very frequently and is a real pain. Sometimes i cant make like 4 steps. Can anybody help or link to a thread where there are informations about this kind of bug? I should add it only happens to some of my characters, not all

First I want to know

1. Which server?
2. What's your ping on the server?

If this is on WoTLK realm, I get these 'rubberbanding' on about 400 ms ping, and there's really nothing much I can do

If this is on Frostwolf (and maybe Neltharion), check your character speed. I had this bug where the server acknowledged me as dead on selection screen, yet I'm alive and well. The thing is I have ghost speed (150%) and the server got confused by this, rubberbanding my toon as I move due to possible speedhack. This is fixed by dying for real on a valid spot (starting zone is where this is prone to happen, my case was when I was logging my gnome inside Gnomeregan due to cleanup quest vehicle being bugged) or if you have mount, remount and dismount immediately. Both should reset your speed to normal. Forewarning, some zones might transport you to a faraway graveyard when you die. Tinker Town for instance doesn't have any graveyard and will send you to the 'point of origin' : Westfall

If this is not the case, then it's probably your connection being insufficient. See the WoTLK case above