Different widget appearance on different machines

[Tyler Hepworth <raklet gmail com>]

I am using Gtk2 1.020 on Windows (Wayne Keenan's distribution).  I
downloaded and installed all of his libraries on two Windows XP
machines.  Everything runs just fine on both platforms.  However, the
TreeView widget on one machine displays white triangles for
expand/collapse operations.  The TreeView widget displays +/- signs in
a little box on the other machine.  Any ideas why this is different
for each machine?

Thanks,

Tyler Hepworth