diff --git a/src/actor.h b/src/actor.h
index 96aa7efd2f..939160ee06 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -330,6 +330,7 @@ enum
 	MF6_DONTCORPSE		= 0x02000000,	// [RC] Don't autoset MF_CORPSE upon death and don't force Crash state change.
 	MF6_POISONALWAYS	= 0x04000000,	// Always apply poison, even when target can't take the damage.
 	MF6_DOHARMSPECIES	= 0x08000000,	// Do hurt one's own species with projectiles.
+	MF6_INTRYMOVE		= 0x10000000,	// Executing P_TryMove
 
 // --- mobj.renderflags ---
 
@@ -775,6 +776,8 @@ public:
 	const char *GetTag(const char *def = NULL) const;
 	void SetTag(const char *def);
 
+	// Triggers SECSPAC_Exit/SECSPAC_Enter and related events if oldsec != current sector
+	void CheckSectorTransition(sector_t *oldsec);
 
 // info for drawing
 // NOTE: The first member variable *must* be x.
diff --git a/src/p_map.cpp b/src/p_map.cpp
index 06ea2d655e..2c4cbe1ea4 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -307,6 +307,7 @@ void P_FindFloorCeiling (AActor *actor, bool onlyspawnpos)
 bool P_TeleportMove (AActor *thing, fixed_t x, fixed_t y, fixed_t z, bool telefrag)
 {
 	FCheckPosition tmf;
+	sector_t *oldsec = thing->Sector;
 	
 	// kill anything occupying the position
 		
@@ -405,6 +406,13 @@ bool P_TeleportMove (AActor *thing, fixed_t x, fixed_t y, fixed_t z, bool telefr
 	thing->PrevY = y;
 	thing->PrevZ = z;
 
+	// If this teleport was caused by a move, P_TryMove() will handle the
+	// sector transition messages better than we can here.
+	if (!(thing->flags6 & MF6_INTRYMOVE))
+	{
+		thing->CheckSectorTransition(oldsec);
+	}
+
 	return true;
 }
 
@@ -1677,6 +1685,7 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 	{
 		thing->z = onfloor->ZatPoint (x, y);
 	}
+	thing->flags6 |= MF6_INTRYMOVE;
 	if (!P_CheckPosition (thing, x, y, tm))
 	{
 		AActor *BlockingMobj = thing->BlockingMobj;
@@ -1704,6 +1713,7 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 		if (!(tm.thing->flags2 & MF2_PASSMOBJ) || (i_compatflags & COMPATF_NO_PASSMOBJ))
 		{
 			thing->z = oldz;
+			thing->flags6 &= ~MF6_INTRYMOVE;
 			return false;
 		}
 	}
@@ -1813,6 +1823,7 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 				{ // Can't move over a dropoff unless it's been blasted
 				  // [GZ] Or missile-spawned
 					thing->z = oldz;
+					thing->flags6 &= ~MF6_INTRYMOVE;
 					return false;
 				}
 			}
@@ -1821,7 +1832,11 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 				// special logic to move a monster off a dropoff
 				// this intentionally does not check for standing on things.
 				if (thing->floorz - tm.floorz > thing->MaxDropOffHeight ||
-					thing->dropoffz - tm.dropoffz > thing->MaxDropOffHeight) return false;
+					thing->dropoffz - tm.dropoffz > thing->MaxDropOffHeight)
+				{
+					thing->flags6 &= ~MF6_INTRYMOVE;
+					return false;
+				}
 			}
 		}
 		if (thing->flags2 & MF2_CANTLEAVEFLOORPIC
@@ -1829,6 +1844,7 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 				|| tm.floorz - thing->z != 0))
 		{ // must stay within a sector of a certain floor type
 			thing->z = oldz;
+			thing->flags6 &= ~MF6_INTRYMOVE;
 			return false;
 		}
 		
@@ -1843,6 +1859,7 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 				thing->velx = 0;
 				thing->vely = 0;
 				thing->z = oldz;
+				thing->flags6 &= ~MF6_INTRYMOVE;
 				return false;
 			}
 		} 
@@ -1869,7 +1886,10 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 	if (thing->BounceFlags & BOUNCE_MBF &&  // killough 8/13/98
 			!(thing->flags & (MF_MISSILE|MF_NOGRAVITY)) &&
 			!thing->IsSentient() && tm.floorz - thing->z > 16*FRACUNIT)
-	return false; // too big a step up for MBF bouncers under gravity
+	{ // too big a step up for MBF bouncers under gravity
+		thing->flags6 &= ~MF6_INTRYMOVE;
+		return false;
+	}
 
 	// the move is ok, so link the thing into its new position
 	thing->UnlinkFromWorld ();
@@ -1896,6 +1916,7 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 	// [RH] Don't activate anything if just predicting
 	if (thing->player && (thing->player->cheats & CF_PREDICTING))
 	{
+		thing->flags6 &= ~MF6_INTRYMOVE;
 		return true;
 	}
 
@@ -1967,34 +1988,13 @@ bool P_TryMove (AActor *thing, fixed_t x, fixed_t y,
 	}
 
 	// [RH] If changing sectors, trigger transitions
-	if (oldsec != newsec)
-	{
-		if (oldsec->SecActTarget)
-		{
-			oldsec->SecActTarget->TriggerAction (thing, SECSPAC_Exit);
-		}
-		if (newsec->SecActTarget)
-		{
-			int act = SECSPAC_Enter;
-			if (thing->z <= newsec->floorplane.ZatPoint (thing->x, thing->y))
-			{
-				act |= SECSPAC_HitFloor;
-			}
-			if (thing->z + thing->height >= newsec->ceilingplane.ZatPoint (thing->x, thing->y))
-			{
-				act |= SECSPAC_HitCeiling;
-			}
-			if (newsec->heightsec &&
-				thing->z == newsec->heightsec->floorplane.ZatPoint (thing->x, thing->y))
-			{
-				act |= SECSPAC_HitFakeFloor;
-			}
-			newsec->SecActTarget->TriggerAction (thing, act);
-		}
-	}
+	thing->CheckSectorTransition(oldsec);
+	thing->flags6 &= ~MF6_INTRYMOVE;
 	return true;
 
 pushline:
+	thing->flags6 &= ~MF6_INTRYMOVE;
+
 	// [RH] Don't activate anything if just predicting
 	if (thing->player && (thing->player->cheats & CF_PREDICTING))
 	{
diff --git a/src/p_mobj.cpp b/src/p_mobj.cpp
index 562d0947e0..ab69bbb197 100644
--- a/src/p_mobj.cpp
+++ b/src/p_mobj.cpp
@@ -3362,6 +3362,42 @@ void AActor::Tick ()
 	}
 }
 
+//==========================================================================
+//
+// AActor :: CheckSectorTransition
+//
+// Fire off some sector triggers if the actor has changed sectors.
+//
+//==========================================================================
+
+void AActor::CheckSectorTransition(sector_t *oldsec)
+{
+	if (oldsec != Sector)
+	{
+		if (oldsec->SecActTarget != NULL)
+		{
+			oldsec->SecActTarget->TriggerAction(this, SECSPAC_Exit);
+		}
+		if (Sector->SecActTarget != NULL)
+		{
+			int act = SECSPAC_Enter;
+			if (z <= Sector->floorplane.ZatPoint(x, y))
+			{
+				act |= SECSPAC_HitFloor;
+			}
+			if (z + height >= Sector->ceilingplane.ZatPoint(x, y))
+			{
+				act |= SECSPAC_HitCeiling;
+			}
+			if (Sector->heightsec != NULL && z == Sector->heightsec->floorplane.ZatPoint(x, y))
+			{
+				act |= SECSPAC_HitFakeFloor;
+			}
+			Sector->SecActTarget->TriggerAction(this, act);
+		}
+	}
+}
+
 //==========================================================================
 //
 // AActor::UpdateWaterLevel