diff --git a/ChangeLog b/ChangeLog
index 9f4b7f3027..b8663a78ec 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2005-11-21  Andy Wingo  <wingo@pobox.com>
 
+	* gst/gsterror.c (_gst_core_errors_init):
+	* gst/gsterror.h (GST_CORE_ERROR_MISSING_PLUGIN): New error
+	category.
+
 	* gst/Makefile.am (gst_headers): Add glib-compat.h.
 	(noinst_HEADERS): noinst the -private.
 
diff --git a/gst/gsterror.c b/gst/gsterror.c
index 143f0a39d9..7b837c3175 100644
--- a/gst/gsterror.c
+++ b/gst/gsterror.c
@@ -149,6 +149,8 @@ _gst_core_errors_init (void)
   TABLE (t, CORE, CAPS,
       N_("Internal GStreamer error: caps problem." FILE_A_BUG));
   TABLE (t, CORE, TAG, N_("Internal GStreamer error: tag problem." FILE_A_BUG));
+  TABLE (t, CORE, MISSING_PLUGIN,
+      N_("Your GStreamer installation is missing a plug-in."));
 
   return t;
 }
diff --git a/gst/gsterror.h b/gst/gsterror.h
index e200c88e6b..b1952d359b 100644
--- a/gst/gsterror.h
+++ b/gst/gsterror.h
@@ -50,6 +50,7 @@ G_BEGIN_DECLS
  * @GST_CORE_ERROR_SEEK: used for seek-related errors.
  * @GST_CORE_ERROR_CAPS: used for caps-related errors.
  * @GST_CORE_ERROR_TAG: used for negotiation-related errors.
+ * @GST_CORE_ERROR_MISSING_PLUGIN: used if a plugin is missing.
  * @GST_CORE_ERROR_NUM_ERRORS: the number of core error types.
  *
  * Core errors are errors inside the core GStreamer library.
@@ -69,6 +70,7 @@ typedef enum
   GST_CORE_ERROR_SEEK,
   GST_CORE_ERROR_CAPS,
   GST_CORE_ERROR_TAG,
+  GST_CORE_ERROR_MISSING_PLUGIN,
   GST_CORE_ERROR_NUM_ERRORS
 } GstCoreError;