Has anyone experienced problems with list boxes in containers?

I am using multiple containers in one single form which only become enabled/visible when required. Containers that contain list boxes will not behave correctly when clicked on if another container - containing a list box - has been previously used. ie - the currently used container still thinks there is a list box in front of it and refuses to allow mouse action on it.

This can be easily recreated by putting two containers (each containing a list box) on a form, then programmatically put one in front of the other, and the one that was loaded first will be slightly unusable - even though it is in front. Obviously the list boxes are in the same position on the screen.