diff --git a/ChangeLog b/ChangeLog
index 41f7a34e4..8c06ab436 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2003-08-22  Moritz Bunkus  <moritz@bunkus.org>
+
+        * mkvmerge: Bugfix: If a subtitle packet was the last packet in a
+        cluster then its duration was not written resulting in a broken file.
+
 2003-08-21  Moritz Bunkus  <moritz@bunkus.org>
 
         * mkvinfo: Added support for the following elements:
diff --git a/src/cluster_helper.cpp b/src/cluster_helper.cpp
index e0be4fd44..e62a8eae3 100644
--- a/src/cluster_helper.cpp
+++ b/src/cluster_helper.cpp
@@ -477,6 +477,9 @@ int cluster_helper_c::render() {
     last_source = source;
   }
 
+  for (k = 0, block_duration = 0; k < durations.size(); k++)
+    block_duration += durations[k];
+
   if (elements_in_cluster > 0) {
     def_duration = last_source->get_track_default_duration_ns() / 1000000;
     if ((block_duration != 0) && (def_duration != block_duration)) {