firefox3 with high latencies when acting with mouse or keyboard and graphics refresh

[O. Hartmann]

Hello,
got a problem since yesterday after having done a lot of updates 
(ports): on all of my FreeBSD 8.0-CURRENT/amd64 boxes firefox does have 
enormous high latencies when typing in or moving the mouse or popping up 
the window icon or down. Since this happens on all of 8.0-CUR/amd boxes, 
I guess it has something to do with an upgrade of the ports.

I reinstalled firefox twice, but without success, so I want to ask for 
some hints..

Regards,
Oliver