Modal Popup extender in accordion pane

I have a modal popup extender in an accordion pane. Here the code of the modal popup extender:

<atlasToolkit:ModalPopupExtender  ID="ModalPopupExtender" runat="server">        <atlasToolkit:ModalPopupProperties TargetControlID="btnDeleteTeacher" PopupControlID="pnlDeleteTeacher" BackgroundCssClass="modalBackground" DropShadow="true" OkControlID="OkDeleteTeacher" CancelControlID="CancelDeleteTeacher" OnOkScript="deleteteacher()"/>    </atlasToolkit:ModalPopupExtender>

  this modalpopup extender is in an accordion pane and it does popup when i click on the button btnDeleteTeacher, but if i then confirm within the modal popup extender the specified function deleteteacher is not called. is there a workaround or is it just not possible to use a modal popup extender within a accordion plane?

 thx in advance,

obachem