Pass variable from submenu to main menu context

[Robert Kliewer]

I'm trying to set a variable ('superusers' specifically) from a submenu in
grub.  When I return to the main grub menu the variable is reverted to it's
previous value.  I know export works to keep variables from the main menu
into submenus, but the reverse does not appear to be true.  I also tried
using an envblock to store variable changes, but I cannot force the main
menu to read when the submenu returns.  Is there any way to maintain a
variable change in a submenu into the main menu?  Thanks.

Rob