Combo Box TextChanged event not fired if value is not in the list

Hi,

I have an Ajax Toolkit Combo Box in DropDown Style (to allow user to enter custom value). The event SelectedIndexChanged and TextChanged works fine if the user select an item of the list of the combo box.

The problem is if the user enter a value that is not in the list of the item of the combo box, the event SelectedIndexChanged nor TextChanged are fired. Is there a way to "force" those events to be fired?

Thanks