Mobs blinking out randomly

Hey folks,
When I play GW/prof(it that matters), it seems every battle has at least 1 mob 'blinking out' and reappearing in a nearby area.
I'll be fighting the mob, it will then move a little, disappear, then appear nearby. Hope that's coming accross clearly.
My character follows, but it's just kinda odd.

My system is:
P4- 1.6 I think
1 gig ram
NVidia 6600GT
*DSL connection *added*

The game plays wonderfully, the scenery is beautiful. It's just that 'popping' that occurs- occassionally. Hardly game breaking, but wondering if I can correct this issue.
Is this considered 'lag'?

Thanks in advance,
A

Yes, it comes down to the client not being updated with the correct location of an enemy, it's pretty normal.

I kind of figured that was what was going on, just wanted some reassurance. I appreciate the reply.
-A