tagline and copyright headers in a one-page piece

[Graham Percival]

Is there any way to display both a \header{tagline} and \header{copyright}
when the music is only one page?  Currently LilyPond treats a one-page
piece as being just the last page (so it displays the tagline but not
copyright).

I tried looking at share/lilypond/tex/source/titledefs.tex , but I don't
know how to add "if only one page, then
address@hidden
\mbox{}\makelilypondtagline}}%
"


I _could_ make tagline into "copyright string \\ tagline string" for
the one-page piece, but then I couldn't have a standardized header
for all my pieces.

- Graham Percival