diff --git a/docs/rh-log.txt b/docs/rh-log.txt
index 344a2a1b9c..8c839701c0 100644
--- a/docs/rh-log.txt
+++ b/docs/rh-log.txt
@@ -1,4 +1,7 @@
 August 4, 2009
+- Added the MF6_STEPMISSILE flag so that the Whirlwind can "walk" up steps.
+- Changed the dword definition of PalEntry to uint32 so that it has one
+  consistent definition across all source files.
 - Swapped the order of floor and ceiling moves in DElevator::Tick() so that
   if an elevator contains an actor exactly the same height as it, it will not
   be blocked.
diff --git a/src/actor.h b/src/actor.h
index 073bc867a1..1085f1650a 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -311,6 +311,7 @@ enum
 	MF6_NOFEAR			= 0x00000010,	// Not scared of frightening players
 	MF6_BUMPSPECIAL		= 0x00000020,	// Actor executes its special when being collided (as the ST flag)
 	MF6_DONTHARMSPECIES = 0x00000040,	// Don't hurt one's own species with explosions (hitscans, too?)
+	MF6_STEPMISSILE		= 0x00000080,	// Missile can "walk" up steps
 
 
 // --- mobj.renderflags ---
diff --git a/src/doomtype.h b/src/doomtype.h
index 08f187aeb5..2748f18273 100644
--- a/src/doomtype.h
+++ b/src/doomtype.h
@@ -155,9 +155,9 @@ enum
 struct PalEntry
 {
 	PalEntry () {}
-	PalEntry (DWORD argb) { d = argb; }
-	operator DWORD () const { return d; }
-	PalEntry &operator= (DWORD other) { d = other; return *this; }
+	PalEntry (uint32 argb) { d = argb; }
+	operator uint32 () const { return d; }
+	PalEntry &operator= (uint32 other) { d = other; return *this; }
 	PalEntry InverseColor() const { PalEntry nc; nc.a = a; nc.r = 255 - r; nc.g = 255 - g; nc.b = 255 - b; return nc; }
 #ifdef WORDS_BIGENDIAN
 	PalEntry (BYTE ir, BYTE ig, BYTE ib) : a(0), r(ir), g(ig), b(ib) {}
@@ -168,7 +168,7 @@ struct PalEntry
 		{
 			BYTE a,r,g,b;
 		};
-		DWORD d;
+		uint32 d;
 	};
 #else
 	PalEntry (BYTE ir, BYTE ig, BYTE ib) : b(ib), g(ig), r(ir), a(0) {}
@@ -179,7 +179,7 @@ struct PalEntry
 		{
 			BYTE b,g,r,a;
 		};
-		DWORD d;
+		uint32 d;
 	};
 #endif
 };
diff --git a/src/p_map.cpp b/src/p_map.cpp
index 5a4e75518e..f29d1a0bd7 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -1606,7 +1606,7 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 			{ // too big a step up
 				goto pushline;
 			}
-			else if ((thing->flags & MF_MISSILE) && tm.floorz > thing->z)
+			else if ((thing->flags & MF_MISSILE)&& !(thing->flags6 && MF6_STEPMISSILE) && tm.floorz > thing->z)
 			{ // [RH] Don't let normal missiles climb steps
 				goto pushline;
 			}
@@ -1910,7 +1910,7 @@ bool P_CheckMove(AActor *thing, fixed_t x, fixed_t y)
 			{ // too big a step up
 				return false;
 			}
-			else if ((thing->flags & MF_MISSILE) && tm.floorz > newz)
+			else if ((thing->flags & MF_MISSILE) && !(thing->flags6 && MF6_STEPMISSILE) && tm.floorz > newz)
 			{ // [RH] Don't let normal missiles climb steps
 				return false;
 			}
diff --git a/src/thingdef/thingdef_data.cpp b/src/thingdef/thingdef_data.cpp
index 7e3d25780e..84c814b29e 100644
--- a/src/thingdef/thingdef_data.cpp
+++ b/src/thingdef/thingdef_data.cpp
@@ -217,6 +217,7 @@ static FFlagDef ActorFlags[]=
 	DEFINE_FLAG(MF6, NOFEAR, AActor, flags6),
 	DEFINE_FLAG(MF6, BUMPSPECIAL, AActor, flags6),
 	DEFINE_FLAG(MF6, DONTHARMSPECIES, AActor, flags6),
+	DEFINE_FLAG(MF6, STEPMISSILE, AActor, flags6),
 
 	// Effect flags
 	DEFINE_FLAG(FX, VISIBILITYPULSE, AActor, effects),
diff --git a/wadsrc/static/actors/heretic/ironlich.txt b/wadsrc/static/actors/heretic/ironlich.txt
index f9cfa3a61e..4b7e0ff17b 100644
--- a/wadsrc/static/actors/heretic/ironlich.txt
+++ b/wadsrc/static/actors/heretic/ironlich.txt
@@ -154,6 +154,7 @@ ACTOR Whirlwind native
 	-ACTIVATEMCROSS
 	+SEEKERMISSILE
 	+EXPLOCOUNT
+	+StepMissile
 	RenderStyle Translucent
 	Alpha 0.4