Constant, persistent lags

Hi,

I tried playing on Blackrock and Icecrown but had to stop both because of unplayable lags.

In Blackrock, shopping zones spike to 14-3k MS. When I enter battlegrounds, it drops down to 800ms.
In Icecrown, starting zones start around 100ms but quickly went up and stayed at 260ms.

Both are really unplayable. Have reset my router, tested internet speed - all is good. I am based in East Europe.

Anyone know if this is persistent? Is this a peak time problem? Any ideas?

Thanks!