[syslinux] menu.c32, submenus

[Eugene Pressley]

I am trying to create submenus, or more specifically a single submenu, using PXELINUX and the menu.c32.  I have a tftp share with a basic config:

/ (root of tftp)
pxelinux.0
menu.c32
/diskdiag (dir)
/diskdiag/dskdiag.0
/pxelinux.cfg (dir)
/pxelinux.cfg/default
/pxelinux.cfg/dskdiag


one of the menu items in /pxelinux.cfg/default is as follows:
LABEL DISKDIAG
     MENU LABEL [^B] Disk Diagnostics Menu
     KERNEL \diskdiag\dskdiag.0

one of the menu items in /pxelinux.cfg/dskdiag is as follows:
LABEL DISKDIAG
     MENU LABEL [^M] Return to top menu
     KERNEL \pxelinux.0

The file dskdiag.0 if a copy of pxelinux.0 that I hex edited changing default to dskdiag.  

When I run this setup default menu is displayed and I can choose the submenu (dskdiag).  The submenu is then displayed, but when I choose "M" to go back to the top menu the submenu (dskdiag) is redisplayed.  Any one have any thoughts on what is going wrong?