Box round multiple markup objects?

[Jennifer Clark]

Hi folks,

Is it possible to create a box round multiple markup objects? For 
example, in the code below, when I tried using the \box directive, it 
placed individual boxes round each element. I'd like it to make a single 
box round the whole lot.

  b4^\markup {\hspace #8.0 \italic \bold {"To " \hspace #1.0 \raise 
#1.0 \fontsize #2 \musicglyph #"scripts.coda" "Coda"}}

I can't seem to find anything related to \box about this in the manual. 
Any ideas would be much appreciated.

Jennifer