Problem with MessageDialog boxes

[Jim Charlton <charltn gmail com>]

I have been trying to compile some gtkmm code with 
Gtk::MessageDialog().  The icons do not appear and the buttons are 
packed full width of the message box.

Running gtk3-demo shows the same problem.

I am using libgtk-3.0 version number 1401.5.0.  Older versions of 
libraries seem to work OK.

Any hints as to what I might do to get my messagedialog boxes back to 
normal (other than using an older version of the libraries)?

jim...   Jim Charlton