linux kernel boot parameters for just one menu item

[s harding]

OK. I give up. I need help.

How do I append an item to the linux kernel boot parameters for *just*one* menu 
item in GRUB2?  I want to have two linux menu items. Same partition, same 
kernel, just with different kernel command lines.

GRUB_CMDLINE_LINUX doesn't help me since it applies to all standard linux menu 
lines.

I have created a new custom menu item based on 40_custom. Text appended to its 
'linux /boot/linux'... line does not seem to get through.


The option I am trying to pass is 'init=/sbin/special_init'. I want to run a 
non-default init while retaining the ability to revert to the standard one. I 
am obviously being stupid, but I just can't see how.