* emacs-lisp/package.el (package-built-in-p): Handle `emacs' package.

Fixes: debbugs:11410

lisp/ChangeLog

+2012-05-06  Chong Yidong  <cyd@gnu.org>
+
+	* emacs-lisp/package.el (package-built-in-p): Handle the `emacs'
+	package (Bug#11410).
+
 2012-05-05  Chong Yidong  <cyd@gnu.org>
 
 	* emacs-lisp/package.el (package-buffer-info): Avoid putting local

lisp/emacs-lisp/package.el

@@ -469,8 +469,11 @@ NAME and VERSION are both strings."
 Optional arg MIN-VERSION, if non-nil, should be a version list
 specifying the minimum acceptable version."
   (require 'finder-inf nil t) ; For `package--builtins'.
-  (let ((elt (assq package package--builtins)))
-    (and elt (version-list-<= min-version (package-desc-vers (cdr elt))))))
+  (if (eq package 'emacs)
+      (version-list-<= min-version (version-to-list emacs-version))
+    (let ((elt (assq package package--builtins)))
+      (and elt (version-list-<= min-version
+				(package-desc-vers (cdr elt)))))))
 
 ;; This function goes ahead and activates a newer version of a package
 ;; if an older one was already activated.  This is not ideal; we'd at