=== modified file 'lisp/vc/ediff-vers.el'
--- lisp/vc/ediff-vers.el	2011-01-25 04:08:28 +0000
+++ lisp/vc/ediff-vers.el	2011-03-10 04:03:04 +0000
@@ -59,6 +59,14 @@
       'vc-working-revision
     'vc-workfile-version))
 
+
+(defun ediff-revision-internal (rev1 rev2 &optional startup-hook)
+  ;; Call backend-specific ediff function. Uses `vc.el' or `rcs.el'
+  ;; depending on `ediff-version-control-package'."
+  (funcall
+   (intern (format "ediff-%S-internal" ediff-version-control-package))
+   rev1 rev2 startup-hook))
+
 ;; VC.el support
 
 (eval-when-compile

=== modified file 'lisp/vc/ediff.el'
--- lisp/vc/ediff.el	2011-01-25 04:08:28 +0000
+++ lisp/vc/ediff.el	2011-03-10 04:03:14 +0000
@@ -1408,8 +1408,7 @@
 (defun ediff-revision (&optional file startup-hooks)
   "Run Ediff by comparing versions of a file.
 The file is an optional FILE argument or the file entered at the prompt.
-Default: the file visited by the current buffer.
-Uses `vc.el' or `rcs.el' depending on `ediff-version-control-package'."
+Default: the file visited by the current buffer."
   ;; if buffer is non-nil, use that buffer instead of the current buffer
   (interactive "P")
   (if (not (stringp file))
@@ -1435,11 +1434,7 @@
 	   (format "Revision 2 to compare (default %s's current state): "
 		   (file-name-nondirectory file))))
     (ediff-load-version-control)
-    (funcall
-     (intern (format "ediff-%S-internal" ediff-version-control-package))
-     rev1 rev2 startup-hooks)
-    ))
-
+    (ediff-revision-internal rev1 rev2 startup-hooks)))
 
 ;;;###autoload
 (defalias 'erevision 'ediff-revision)

=== modified file 'lisp/vc/vc.el'
--- lisp/vc/vc.el	2011-03-07 08:56:30 +0000
+++ lisp/vc/vc.el	2011-03-10 04:04:32 +0000
@@ -1681,6 +1681,35 @@
 		      (called-interactively-p 'interactive))))
 
 ;;;###autoload
+(defun vc-ediff (historic &optional not-urgent)
+  "Display diffs between revisions of a file using ediff.
+Normally this compares the currently selected file with its
+working revision. With the prefix argument HISTORIC, it reads two revision
+designators specifying which revisions to compare.
+
+The optional argument NOT-URGENT non-nil means it is ok to say no
+to saving the buffer."
+  (interactive (list current-prefix-arg t))
+  (when buffer-file-name (vc-buffer-sync not-urgent))
+  (let* ((vc-fileset (vc-deduce-fileset not-urgent))
+         (files (cadr vc-fileset))
+         (first (car files)))
+      (cond
+       ;; FIXME: Only supports one selected file (for now?).
+       ;; Alternatively, we could spin off a separate ediff session
+       ;; for each of the selected files.
+       ((= (length files) 1)
+        (if historic
+            ;; Let user select revisions to compare.
+            (ediff-revision first)
+          (find-file first)
+          ;; With empty arguments, function compares latest version of
+          ;; current buffer's file with current buffer.
+          (ediff-revision-internal "" "")))
+       (t
+        (error "`vc-ediff' does not support selecting more than one file!")))))
+
+;;;###autoload
 (defun vc-root-diff (historic &optional not-urgent)
   "Display diffs between VC-controlled whole tree revisions.
 Normally, this compares the tree corresponding to the current