I'm trying to use a RadGrid inside a modal popup created with the AJAX Control Toolkit's ModalPopupExtender control. However, when I click on the column filter menu provided by the RadGrid, the context menu shows up behind the modal popup. I've tried adjusting the z-order style of the both the menu and the popup by using CSS classes, but both seem to use inline styles to set their z-indexes. The popup uses a value of 10000, while the RadGrid filter menu uses a value of 7000. Is there any way I can set the z-index value the menu uses, so that it shows up above the popup?