=== modified file 'lisp/progmodes/grep.el'
--- lisp/progmodes/grep.el	2011-02-10 19:13:31 +0000
+++ lisp/progmodes/grep.el	2011-08-31 22:25:40 +0000
@@ -956,7 +956,7 @@
 		      dir
 		      (concat
 		       (and grep-find-ignored-directories
-			    (concat (shell-quote-argument "(")
+			    (concat "-type d " (shell-quote-argument "(")
 				    ;; we should use shell-quote-argument here
 				    " -path "
 				    (mapconcat