Re: nil

[Richard Stallman]

    Perhaps this menu item should invoke a command which funcalls the
    value of some buffer-local variable which the major mode should
    initialize? For example, cperl-mode could set, say, gud-command-name
    to perldb, and java-mode could set it to jdb. Etc.

It would be a reasonable idea.  For now, I will change the menu item
string since that is quick.  If someone wants to do this more powerful
feature, we can install that instead.