diff --git a/docs/rh-log.txt b/docs/rh-log.txt
index e17e6ddfb..74b6e584c 100644
--- a/docs/rh-log.txt
+++ b/docs/rh-log.txt
@@ -1,4 +1,5 @@
 June 30, 2009
+- Fixed: clearflags did not clear flags6.
 - Added A_SetAngle, A_SetPitch, A_ScaleVelocity, and A_ChangeVelocity.
 - Enough with this "momentum" garbage. What Doom calls "momentum" is really
   velocity, and now it's known as such. The actor variables momx/momy/momz
diff --git a/src/thingdef/thingdef_properties.cpp b/src/thingdef/thingdef_properties.cpp
index 804ae3687..3531b517a 100644
--- a/src/thingdef/thingdef_properties.cpp
+++ b/src/thingdef/thingdef_properties.cpp
@@ -1011,8 +1011,12 @@ DEFINE_PROPERTY(species, S, Actor)
 //==========================================================================
 DEFINE_PROPERTY(clearflags, 0, Actor)
 {
-	defaults->flags=defaults->flags3=defaults->flags4=defaults->flags5=0;
-	defaults->flags2&=MF2_ARGSDEFINED;	// this flag must not be cleared
+	defaults->flags =
+		defaults->flags3 =
+		defaults->flags4 =
+		defaults->flags5 =
+		defaults->flags6 = 0;
+	defaults->flags2 &= MF2_ARGSDEFINED;	// this flag must not be cleared
 }
 
 //==========================================================================