Description of problem:
On the dual-head page, the drop-down lists are being displayed in a very wide
format, wider than the window itself.  You cannot edit your settings until you
manually widen the window.

Version-Release number of selected component (if applicable):
system-config-display-1.0.37-2

How reproducible:
always

Steps to Reproduce:
1.  open system-config-display
2.  switch to dual-head tab
  
Actual results:
controls too wide for screen (see screenshot)