this bug was resolved in Fx3.6b1 but seems to have returned in Fx3.6b2, I have just updated to 3.6b3 and the bug is also present in this build
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.2b3) Gecko/20091115 Firefox/3.6b3 (.NET CLR 3.5.30729)
this bug was resolved in Fx3.6b1 but seems to have returned in Fx3.6b2,
I have just updated to 3.6b3 and the bug is also present in this build
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.2b3) Gecko/20091115 Firefox/3.6b3 (.NET CLR 3.5.30729)