question about combo box

[yeajchao <yeajchao yahoo com cn>]

Hello all
    First,I apologize for my terribly poor English
    I  have a question about GtkcomboBox
    You know,every combobox have a GList which stores
some optional item.
    My problem is about the GList.
    When I click the triangle to pull down the list,
         and move my mouse to select item,
         the highlight item didn't change from one
item to another when my mouse moves from one item to
another.
    The thing I want is that: when my mouse is on item
A,the highlight item is item A; when my mouse is on
item B,the highlight itme is item B.
    How can i do that ?
    Any help would be much appreciated!


		
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