diff --git a/docs/rh-log.txt b/docs/rh-log.txt
index 24a83251cd..b00386464e 100644
--- a/docs/rh-log.txt
+++ b/docs/rh-log.txt
@@ -1,4 +1,7 @@
-March 24, 2009  (Changes by Graf Zahl)
+March 25, 2009  (Changes by Graf Zahl)
+- Fixed: Implicitly defined clusters were not initialized when being created.
+
+March 24, 2009  (Changes by Graf Zahl)
 - Fixed: Item tossing did not work anymore.
 
 March 23, 2009  (Changes by Graf Zahl)
diff --git a/src/g_mapinfo.cpp b/src/g_mapinfo.cpp
index face9f5d9c..d05321c7f2 100644
--- a/src/g_mapinfo.cpp
+++ b/src/g_mapinfo.cpp
@@ -948,6 +948,7 @@ DEFINE_MAP_OPTION(cluster, true)
 	{
 		unsigned int clusterindex = wadclusterinfos.Reserve(1);
 		cluster_info_t *clusterinfo = &wadclusterinfos[clusterindex];
+		clusterinfo->Reset();
 		clusterinfo->cluster = parse.sc.Number;
 		if (parse.HexenHack)
 		{