Lately I've gotten this error on a few servers:

It reads: Fatal-ISV: (../../engine/bricks/octBatcher.h @ 22)
octVortex::validate - out of range pos.x
Open hitting OK, the game would close.
I've gotten this error when I get on a server, most notably WinterBite, and one of Tezuni's servers.
I'll try to replicate the error and catch the console log later.