diff --git a/ChangeLog b/ChangeLog
index dd445a9bc..6018907ef 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2005-06-16  Moritz Bunkus  <moritz@bunkus.org>
+
+	* mkvmerge: bug fixes: Improved the native MPEG-4 generation a lot
+	(thanks to Haali for testing and pushing me). The codec version
+	string inside the MPEG-4 initialization data is now checked if it
+	indicates "DivX packed bitstream" and changed to not indicate it
+	anymore.
+
 2005-06-07  Moritz Bunkus  <moritz@bunkus.org>
 
 	* mmg: bug fix: If mmg was minimized when it was closed (e.g. with
diff --git a/src/output/p_video.cpp b/src/output/p_video.cpp
index 53237f90f..efc16ada6 100644
--- a/src/output/p_video.cpp
+++ b/src/output/p_video.cpp
@@ -353,6 +353,7 @@ mpeg4_p2_video_packetizer_c::process_non_native(packet_cptr packet) {
       ti.private_data = config_data->grab();
       ti.private_size = config_data->size;
       delete config_data;
+      fix_codec_string();
       set_codec_private(ti.private_data, ti.private_size);
       rerender_track_headers();
 
@@ -404,6 +405,40 @@ mpeg4_p2_video_packetizer_c::process_non_native(packet_cptr packet) {
   return FILE_STATUS_MOREDATA;
 }
 
+void
+mpeg4_p2_video_packetizer_c::fix_codec_string() {
+  static const unsigned char start_code[4] = {0x00, 0x00, 0x01, 0xb2};
+  unsigned char *end_pos;
+  int i, size;
+
+  if ((NULL == ti.private_data) || (0 == ti.private_size))
+    return;
+
+  size = ti.private_size;
+  for (i = 0; 9 < size;) {
+    if (memcmp(&ti.private_data[i], start_code, 4) != 0) {
+      ++i;
+      --size;
+      continue;
+    }
+
+    i += 8;
+    size -= 8;
+    if (strncasecmp((const char *)&ti.private_data[i - 4], "divx", 4) != 0)
+      continue;
+
+    end_pos = (unsigned char *)memchr(&ti.private_data[i], 0, size);
+    if (NULL == end_pos)
+      end_pos = &ti.private_data[i + size];
+
+    --end_pos;
+    if ('p' == *end_pos)
+      *end_pos = 'n';
+
+    return;
+  }
+}
+
 int
 mpeg4_p2_video_packetizer_c::process_native(packet_cptr packet) {
   // Not implemented yet.
diff --git a/src/output/p_video.h b/src/output/p_video.h
index 56ae65b6b..dd149d7fb 100644
--- a/src/output/p_video.h
+++ b/src/output/p_video.h
@@ -95,6 +95,7 @@ protected:
   virtual void flush_frames_maybe(frame_type_e next_frame);
   virtual void flush_frames();
   virtual void extract_aspect_ratio(const unsigned char *buffer, int size);
+  virtual void fix_codec_string();
 };
 
 class mpeg4_p10_video_packetizer_c: public video_packetizer_c {