Combo display in DHTML GRID ATTACHED TO DHTML TABBAR Problem

Hi
I am attaching a Grid which contains Combo (cell type = “co”) to a tab bar.
the combo box is displayed in the grid in IE. But in FIREFOX, the combo is not getting displayed.
I am using the latest free version of dhtmlx tabbar and Grid is version 1.6.

Pls help me to resolve this.

Thanks and regards
Ramesh

Please provide the complete demo to recreate the problem