I heard of several ppl who got this problem on euro mir whenever they accessed WW/ZT server (never on bw or mw server) so Im presuming it must be some IP setting incorrectly written or missing? Connection speed didn't seem to make any difference, some ppl with 56k got it, i got it sometimes on 512k and ppl with 2meg got it, but some people never got it at all regardless of connection.
Alternatively it might have something to do with physical location and distance to the server, if your connection is taking a certain route it may be the fault of neither you or the host but some ISP in the middle somewhere