[Evolution] How to modify toolbar buttons 2.28.3

[George Reeke <reeke mail rockefeller edu>]

Dear colleagues,
   I recently updated my home system to CentOS 6.3, which provides
evolution 2.28.3.  This does not seem to have the buttons for "copy"
and "move" on the main mail toolbar.  I cannot find anywhere in the
documentation or gconf-editor how to configure this toolbar.  Can
someone help me add buttons to perform these functions?  Or just tell
me where to find the code so I can fool around with it?
   [Note:  I recall that with an earlier version of evolution some
years ago, this could be done by modifying some xml code in a directory
somewhere, and I did this and have been happy since, but I no longer
have any notes on how that was done and cannot find anything that
looks relevant in /usr/share/evolution, and anyway, it may be different
now.  Also, please don't tell me 2.28.3 is "ancient" as it is the
version supplied with the very latest RedHat (= CentOS) release and I
have learned to my sorrow that it is not smart to try to update
envolution in that environment.]
   Thanks,
   George Reeke