diff --git a/ChangeLog b/ChangeLog
index ba9c8347..553dda13 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2007-09-27  Marcus Brinkmann  <marcus@g10code.de>
 
+	* assuan-pipe-connect.c (pipe_connect_gpgme): Fix last change.
+
 	* assuan-pipe-connect.c (pipe_connect_gpgme): New function, use it
 	if _ASSUAN_IN_GPGME_BUILD_ASSUAN.
 
diff --git a/doc/ChangeLog b/doc/ChangeLog
index 7328f381..24b2abed 100644
--- a/doc/ChangeLog
+++ b/doc/ChangeLog
@@ -1,3 +1,7 @@
+2007-09-27  Marcus Brinkmann  <marcus@g10code.de>
+
+	* gpgme.texi (Protocols and Engines): Document GPGME_PROTOCOL_UNKNOWN.
+
 2007-09-11  Werner Koch  <wk@g10code.com>
 
 	* gpgme.texi (I/O Callback Example): Typo fix.
diff --git a/doc/gpgme.texi b/doc/gpgme.texi
index 4692d263..fe0ade23 100644
--- a/doc/gpgme.texi
+++ b/doc/gpgme.texi
@@ -748,6 +748,12 @@ This specifies the OpenPGP protocol.
 
 @item GPGME_PROTOCOL_CMS
 This specifies the Cryptographic Message Syntax.
+
+@item GPGME_PROTOCOL_UNKNOWN
+Reserved for future extension.  You may use this to indicate that the
+used protocol is not known to the application.  Currently,
+@acronym{GPGME} does not accept this value in any operation, though,
+except for @code{gpgme_get_protocol_name}.
 @end table
 @end deftp
 
diff --git a/gpgme/ChangeLog b/gpgme/ChangeLog
index 785fcd26..d8e1f96b 100644
--- a/gpgme/ChangeLog
+++ b/gpgme/ChangeLog
@@ -1,5 +1,9 @@
 2007-09-27  Marcus Brinkmann  <marcus@g10code.de>
 
+	* gpgme.h (gpgme_protocol_t): Add GPGME_PROTOCOL_UNKNOWN.
+	* gpgme.c (gpgme_get_protocol_name): Implement support for
+	GPGME_PROTOCOL_UNKNOWN.
+
 	* kdpipeiodevice.h: Fix last change.
 
 	* w32-glib-io.c (_gpgme_io_pipe), w32-qt-io.c (_gpgme_io_pipe),
diff --git a/gpgme/gpgme.c b/gpgme/gpgme.c
index 58439530..a96db530 100644
--- a/gpgme/gpgme.c
+++ b/gpgme/gpgme.c
@@ -208,6 +208,9 @@ gpgme_get_protocol_name (gpgme_protocol_t protocol)
     case GPGME_PROTOCOL_CMS:
       return "CMS";
 
+    case GPGME_PROTOCOL_UNKNOWN:
+      return "unknown";
+
     default:
       return NULL;
     }
diff --git a/gpgme/gpgme.h b/gpgme/gpgme.h
index a4dbcd4a..57bb0116 100644
--- a/gpgme/gpgme.h
+++ b/gpgme/gpgme.h
@@ -300,7 +300,8 @@ gpgme_validity_t;
 typedef enum
   {
     GPGME_PROTOCOL_OpenPGP = 0,  /* The default mode.  */
-    GPGME_PROTOCOL_CMS     = 1
+    GPGME_PROTOCOL_CMS     = 1,
+    GPGME_PROTOCOL_UNKNOWN = 255
   }
 gpgme_protocol_t;