What would be the steps to reproduce, I've not noticed any issues.

Firefox 3.0.4: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.4) Gecko/2008102920 Firefox/3.0.4 (.NET CLR 3.5.30729)
Windows XP SP2
AVG 8.0.176 Definitions: 270.9.12/1824