Is it possible for a ControlContainerTool to allow resizing by dragging the bottom-right corner using the mouse?

I'm adding an UltraGroupBox (which contains other controls) into the ControlContainer. I'd like to allow the user to resize the container. The UltraGroupBox is set to Dock.None and the ControlContainerTool CanSetWidth is set to True.

The ControlContainer was added as a tool to a PopupMenuTool with a PopupStyle of Toolbar. It opens fine, but there doesn't seem to be a way to resize it.

Thanks,

Jim