--- a/lisp/prim/frame.el	Mon Aug 13 09:21:56 2007 +0200
+++ b/lisp/prim/frame.el	Mon Aug 13 09:23:06 2007 +0200
@@ -1034,6 +1034,9 @@
 (defvar temp-buffer-shrink-to-fit t
   "*When non-nil resize temporary output buffers to minimize blank lines.")
 
+(defvar temp-buffer-max-height .5
+  "*Proportion of frame to use for temp windows.")
+
 (defun show-temp-buffer-in-current-frame (buffer)
   "For use as the value of temp-buffer-show-function:
 always displays the buffer in the current frame, regardless of the behavior
@@ -1048,7 +1051,12 @@
       (set-window-start window 1) ; obeys narrowing
       (set-window-point window 1)
       (when temp-buffer-shrink-to-fit
-	(shrink-window-if-larger-than-buffer window))
+        (let* ((temp-window-size (round (* temp-buffer-max-height
+                                           (frame-height (window-frame window)))))
+               (size (window-displayed-height window)))
+          (when (< size temp-window-size)
+            (enlarge-window (- temp-window-size size) nil window)))
+        (shrink-window-if-larger-than-buffer window))
       nil)))
 
 (setq pre-display-buffer-function 'get-frame-for-buffer)