"Flexicious" : not able to change the search functionality dynamically in a data Grid

"Flexicious" a third party component library built for handling very larg data set in DataGrid for flex, The issue is, i am not able to change the search functionality dynamically in a data Grid.

     <flxs:FlexDataGridColumn id="multiselect" dataField="Name" headerText="Name"
        filterControl="NumericTextInput"  headerAlign="center">                                 
        <flxs:headerRenderer>
        <fx:Component>
        <controls:ComboBox change="changeSel(event)" width="10" height="41" dataProvider="outerDocument.searchArray}">                          

<fx:Script>                                             

<![CDATA[
    import com.flexicious.controls.ComboBox;

    import mx.controls.Alert;                               

    public function changeSel(event:Event):void{                                    

    var cbox:ComboBox = event.currentTarget as ComboBox;                                

    if(cbox.selectedItem=="Less Than"){                                         

    outerDocument.multiselect.filterOperation="LessThanEquals";                                 

    //Alert.show(""+outerDocument.multiselect.filterOperation);                             

    }else if(cbox.selectedItem=="Greator Than"){                                        

    outerDocument.multiselect.filterOperation="GreaterThanEquals";                              

    //Alert.show(""+outerDocument.multiselect.filterOperation);                         

    }else if(cbox.selectedItem=="Equal To"){                                        

    outerDocument.multiselect.filterOperation="Equals";                                     

    //Alert.show(""+outerDocument.multiselect.filterOperation);                         

    }else  if(cbox.selectedItem=="Begins With"){                                        

    outerDocument.multiselect.filterOperation="BeginsWith";                                     

    //Alert.show(""+outerDocument.multiselect.filterOperation);                         

    }                                                   

    }                                                   

    ]]>                                         

    </fx:Script>                                        

    </controls:ComboBox>
    </fx:Component> 
    </flxs:headerRenderer>
    </flxs:FlexDataGridColumn>

Now when i select any option from the rendered combobox i am not able to change filteroption, however when i alter the filteroperation it dose show me the changed operatioin but in functionality it doesn't change.

You should call grid.rebuildFilter() after changing the filterOperation