Problem with popup menu in GTK 2

[Dudley Irish <dirish arsmagna com>]

I am building an app with gtk 2.0 (2.0.1) on a RedHat 7.2 system.  I
am trying to get a popup menu to work with a TreeView widget.  I have
used the example given in the documentation to connect the signal and
to call the gtk_menu_popup.  Everything works except that the menu is
only visable as a tiny box which appears to be about 2 pixels on a
side.  Clearly I am doing something wrong.  If you have a simple
example of using gtk_menu_popup or better yet have encountered this
problem and no the solution, please let me know.  In the meantime, I
am going to strip down the application to a simple test case and see
if I am still getting this behaviour.  If so, I will post the test
case for everyone to take a look at.

Thanks in advance,

Dudley Irish