We are investigating this issue and will get back to you as soon as possible.
For now, the following example works fine for us.
We are using Firefox 3.6.6 as well.
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-GB; rv:1.9.2.6) Gecko/20100625 Firefox/3.6.6 ( .NET CLR 3.5.30729; .NET4.0C)
asp.net Chat http://cutesoft.net/ASP.NET+Chat/default.aspx
Web Messenger: http://cutesoft.net/Web-Messenger/default.aspx
asp.net wysiwyg editor: http://cutesoft.net/ASP.NET+WYSIWYG+Editor/default.aspx
asp wysiwyg html editor: http://cutesoft.net/ASP
asp.net Image Gallery: http://cutesoft.net/ASP.NET+Image+Gallery/default.aspx
Live Support: http://cutesoft.net/live-support/default.aspx