Search for a widget that can completion and option_box

[Bernd Demian <Bernd Demian csc-dd de>]

Hi,
excuse my bad english! We are saerching for a widget that combined the
gtk_entry_completion with gtk_combo_box_entry, but we have no success. 
An example is the url widget in firefox. It has more than one
cell_renderer, has
completion and the possibility explicit popup the tree_view.
In all gtk extra widget sets (libsexy, libview, ..) I can't find this
entry typ. In mozilla I can't find the sources.
Can anybody help us.
MfG Bernd