Really tiny/thin borders

[Adam Tauno Williams <awilliam whitemice org>]

With openSUSE 12.2 and GNOME 3.4 and now GNOME 3.6 the edges / corners
of windows and the draggable panes of windows have *REALLY* thin
borders.  It is difficult to resize windows or a pane in a window.

Is there some mechanism to tweak or adjust this?  I assume through
themes, but that is really the only thing that needs to change.