Java Development Tools

I have a af:table which has first column as checkbox. and the column header is a checkbox for SelectAll/UnselectAll.

<af:column id="rh1" width="20px" rowHeader="true" >

                        <f:facet name="header">

                                <af:selectBooleanCheckbox id="selectAllCheckbox"

                                                  autoSubmit="true"

                                                  valueChangeListener="#{opcNotifyBlackoutsView.selectUnselectAll}"/>

                        </f:facet>

                        <af:selectBooleanCheckbox id="rowSelectCheckbox" value="#{opcNotifyBlackoutsView.blackoutNotifyEventsTable.selectedRowKeys.contained}"

                                                  autoSubmit="true"

                                                  valueChangeListener="#{opcNotifyBlackoutsView.updateEventSelect}"/>

</af:column>

Now when i click on selectAll checkbox, all the row checkboxes get selected and when I deselect the SelectAll checkbox all the row checkboxes get unselected. What i need is once i click on selectAll checkbox and all row checboxes get selected, on unselecting one of the row checkboxes, the selectAll checkbox should get unselected.

Thanks,

Gayatri