Defining grobs from a .ly file

[Mike Solomon]

Hey all,
    Is there a way to define grobs from a .ly file?  Something like:

#(define (make-grob grob-entry)
   (let ((complete-grob-entry (completize-grob-entry grob-entry)))
   (set-object-property! (car complete-grob-entry) 'translation-type? list?)
   (set-object-property! (car complete-grob-entry) 'is-grob? #t))
   (set! all-grob-definitions (cons complete-grob-entry
                                    all-grob-definitions))
   (set! all-grob-descriptions (sort all-grob-descriptions alist<?))))

does not work because of certain non-public variables in
all-grob-descriptions and because completize-grob-entry is not public as
well.  Before I propose an enhancement that more or less recreates the above
in scm/define-grobs.scm, I wanted to check and see if anyone knew a better
way of doing it?

Cheers,
Mike