anchor.diff:    (flet ((compute (val default)
   	   (if (eq val :compute) default val)))
       (if (or (eq (pane-user-width pane) :compute)
  -	    (eq (pane-user-height pane) :compute))
  +            (eq (pane-user-height pane) :compute))  
   	(progn
   	  (with-output-recording-options (pane :record t :draw nil)
   	    ;; multiple-value-letf anyone?
  
positive.code: ;;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  ;;; Boston, MA  02111-1307  USA.
  
  ;;; $Id: panes.lisp,v 1.177 2007/01/07 19:53:05 thenriksen Exp $
  
  (in-package :clim-internals)
  
  
negative.code:     (setq viewport (first (sheet-children pane)))
      ;; make the background of the viewport match the background of the
      ;; things scrolled.
      ;; This doesn't appear to work, hence the "gray space" bugs. Actually
      ;; handy for observing when the space requirements get messed up.. -Hefner
      (when (first (sheet-children viewport))
        (setf (slot-value pane 'background)  ;### hmm ...
              (pane-background (first (sheet-children viewport)))))
  