diff --git a/doc/APIchanges b/doc/APIchanges
index 23e568922c4b80e8ab8bdb618d2009ccd8583bc6..6f7d46df9e84ef311fc64c2becc09f317df48833 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -13,6 +13,9 @@ libavutil:   2011-04-18
 
 API changes, most recent first:
 
+2011-12-03 - xxxxxxx - lavu 51.30.0
+  Add AVERROR_BUG.
+
 2011-xx-xx - xxxxxxx - lavu 51.28.1
   Add av_get_alt_sample_fmt() to samplefmt.h.
 
diff --git a/libavutil/avutil.h b/libavutil/avutil.h
index 85c7dbd0639a3aeb38abaf25b7b3020681746858..af43cc5e8f5eed92ee3eedc7d6531b14037493b6 100644
--- a/libavutil/avutil.h
+++ b/libavutil/avutil.h
@@ -153,8 +153,8 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR 51
-#define LIBAVUTIL_VERSION_MINOR 29
-#define LIBAVUTIL_VERSION_MICRO  1
+#define LIBAVUTIL_VERSION_MINOR 30
+#define LIBAVUTIL_VERSION_MICRO  0
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
                                                LIBAVUTIL_VERSION_MINOR, \
diff --git a/libavutil/error.c b/libavutil/error.c
index d296395c092680806e1d51a64459e15b983d95b5..4220aa6da689d2262815057fafc2633738b4ff06 100644
--- a/libavutil/error.c
+++ b/libavutil/error.c
@@ -27,6 +27,7 @@ int av_strerror(int errnum, char *errbuf, size_t errbuf_size)
 
     switch (errnum) {
     case AVERROR_BSF_NOT_FOUND:     errstr = "Bitstream filter not found"                   ; break;
+    case AVERROR_BUG:               errstr = "Internal bug, should not have happened"       ; break;
     case AVERROR_DECODER_NOT_FOUND: errstr = "Decoder not found"                            ; break;
     case AVERROR_DEMUXER_NOT_FOUND: errstr = "Demuxer not found"                            ; break;
     case AVERROR_ENCODER_NOT_FOUND: errstr = "Encoder not found"                            ; break;
diff --git a/libavutil/error.h b/libavutil/error.h
index fa18afcdf1544d91784bf0d2fff304cb143881f1..d3c14657565130c77b32792fd18a2f775c486d89 100644
--- a/libavutil/error.h
+++ b/libavutil/error.h
@@ -45,6 +45,7 @@
 #endif
 
 #define AVERROR_BSF_NOT_FOUND      (-MKTAG(0xF8,'B','S','F')) ///< Bitstream filter not found
+#define AVERROR_BUG                (-MKTAG( 'B','U','G','!')) ///< Internal bug
 #define AVERROR_DECODER_NOT_FOUND  (-MKTAG(0xF8,'D','E','C')) ///< Decoder not found
 #define AVERROR_DEMUXER_NOT_FOUND  (-MKTAG(0xF8,'D','E','M')) ///< Demuxer not found
 #define AVERROR_ENCODER_NOT_FOUND  (-MKTAG(0xF8,'E','N','C')) ///< Encoder not found