diff --git a/src/am_map.cpp b/src/am_map.cpp
index ec7e99859..d2046f33e 100644
--- a/src/am_map.cpp
+++ b/src/am_map.cpp
@@ -1913,12 +1913,13 @@ bool AM_Check3DFloors(line_t *line)
 //=============================================================================
 
 void AM_drawWalls (bool allmap)
-{
-	int i;
-	static mline_t l;
-
-	for (i = 0; i < numlines; i++)
-	{
+{
+	int i;
+	static mline_t l;
+	int lock, color;
+
+	for (i = 0; i < numlines; i++)
+	{
 		l.a.x = lines[i].v1->x >> FRACTOMAPBITS;
 		l.a.y = lines[i].v1->y >> FRACTOMAPBITS;
 		l.b.x = lines[i].v2->x >> FRACTOMAPBITS;
@@ -1948,14 +1949,22 @@ void AM_drawWalls (bool allmap)
 			else if (lines[i].flags & ML_SECRET)
 			{ // secret door
 				if (am_cheat != 0 && lines[i].backsector != NULL)
-					AM_drawMline(&l, SecretWallColor);
-			    else
-					AM_drawMline(&l, WallColor);
-			}
-			else if ((lines[i].special == Teleport ||
-				lines[i].special == Teleport_NoFog ||
-				lines[i].special == Teleport_ZombieChanger ||
-				lines[i].special == Teleport_Line) &&
+					AM_drawMline(&l, SecretWallColor);
+			    else
+					AM_drawMline(&l, WallColor);
+			} else if (lines[i].locknumber > 0) { // [Dusk] specials w/ locknumbers
+				lock = lines[i].locknumber;
+				color = P_GetMapColorForLock(lock);
+				
+				AMColor c;
+				if (color >= 0)	c.FromRGB(RPART(color), GPART(color), BPART(color));
+				else c = LockedColor;
+				
+				AM_drawMline (&l, c);
+			} else if ((lines[i].special == Teleport ||
+				lines[i].special == Teleport_NoFog ||
+				lines[i].special == Teleport_ZombieChanger ||
+				lines[i].special == Teleport_Line) &&
 				(lines[i].activation & SPAC_PlayerActivate) &&
 				am_colorset == 0)
 			{ // intra-level teleporters
@@ -1975,19 +1984,18 @@ void AM_drawWalls (bool allmap)
 					 (lines[i].special == Door_Animated && lines[i].args[3] != 0) ||
 					 (lines[i].special == Generic_Door && lines[i].args[4] != 0))
 			{
-				if (am_colorset == 0 || am_colorset == 3)	// Raven games show door colors
-				{
-					int P_GetMapColorForLock(int lock);
-					int lock;
-
-					if (lines[i].special==Door_LockedRaise || lines[i].special==Door_Animated)
-						lock=lines[i].args[3];
-					else lock=lines[i].args[4];
-
-					int color = P_GetMapColorForLock(lock);
-
-					AMColor c;
-
+				if (am_colorset == 0 || am_colorset == 3)	// Raven games show door colors
+				{
+					int P_GetMapColorForLock(int lock);
+
+					if (lines[i].special==Door_LockedRaise || lines[i].special==Door_Animated)
+						lock=lines[i].args[3];
+					else lock=lines[i].args[4];
+
+					color = P_GetMapColorForLock(lock);
+
+					AMColor c;
+
 					if (color >= 0)	c.FromRGB(RPART(color), GPART(color), BPART(color));
 					else c = LockedColor;
 
diff --git a/src/namedef.h b/src/namedef.h
index a98de3692..6cf7f322c 100644
--- a/src/namedef.h
+++ b/src/namedef.h
@@ -379,12 +379,13 @@ xx(Midtex3d)
 xx(Checkswitchrange)
 xx(Firstsideonly)
 xx(Transparent)	
-xx(Passuse)
-xx(Repeatspecial)
-xx(Conversation)
-
-xx(Playercross)
-xx(Playeruse)
+xx(Passuse)
+xx(Repeatspecial)
+xx(Conversation)
+xx(Locknumber)
+
+xx(Playercross)
+xx(Playeruse)
 xx(Playeruseback)
 xx(Monstercross)
 xx(Impact)
diff --git a/src/p_spec.cpp b/src/p_spec.cpp
index a60751aa2..d0c28bc89 100644
--- a/src/p_spec.cpp
+++ b/src/p_spec.cpp
@@ -57,12 +57,13 @@
 #include "gi.h"
 #include "statnums.h"
 #include "g_level.h"
-#include "v_font.h"
-#include "a_sharedglobal.h"
-#include "farchive.h"
-
-// State.
-#include "r_state.h"
+#include "v_font.h"
+#include "a_sharedglobal.h"
+#include "farchive.h"
+#include "a_keys.h"
+
+// State.
+#include "r_state.h"
 
 #include "c_console.h"
 
@@ -232,12 +233,14 @@ bool P_ActivateLine (line_t *line, AActor *mo, int side, int activationType)
 	BYTE special;
 
 	if (!P_TestActivateLine (line, mo, side, activationType))
-	{
-		return false;
-	}
-	lineActivation = line->activation;
-	repeat = line->flags & ML_REPEAT_SPECIAL;
-	buttonSuccess = false;
+	{
+		return false;
+	}
+	int remote = (line->special != 7 && line->special != 8 && (line->special < 11 || line->special > 14));
+	if (line->locknumber > 0 && !P_CheckKeys (mo, line->locknumber, remote)) return false;
+	lineActivation = line->activation;
+	repeat = line->flags & ML_REPEAT_SPECIAL;
+	buttonSuccess = false;
 	buttonSuccess = P_ExecuteSpecial(line->special,
 					line, mo, side == 1, line->args[0],
 					line->args[1], line->args[2],
diff --git a/src/p_udmf.cpp b/src/p_udmf.cpp
index e1e0f371a..20ef4ffd2 100644
--- a/src/p_udmf.cpp
+++ b/src/p_udmf.cpp
@@ -877,12 +877,17 @@ public:
 				Flag(ld->flags, ML_BLOCKUSE, key); 
 				continue;
 
-			case NAME_blocksight:
-				Flag(ld->flags, ML_BLOCKSIGHT, key); 
-				continue;
-
-			default:
-				break;
+			case NAME_blocksight:
+				Flag(ld->flags, ML_BLOCKSIGHT, key); 
+				continue;
+			
+			// [Dusk] lock number
+			case NAME_Locknumber:
+				ld->locknumber = CheckInt(key);
+				continue;
+
+			default:
+				break;
 			}
 
 			if (!strnicmp("user_", key.GetChars(), 5))
diff --git a/src/r_defs.h b/src/r_defs.h
index 7af5eabde..03c2290c2 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -907,12 +907,13 @@ struct line_t
 	side_t		*sidedef[2];
 	//DWORD		sidenum[2];	// sidenum[1] will be NO_SIDE if one sided
 	fixed_t		bbox[4];	// bounding box, for the extent of the LineDef.
-	slopetype_t	slopetype;	// To aid move clipping.
-	sector_t	*frontsector, *backsector;
-	int 		validcount;	// if == validcount, already checked
-};
-
-// phares 3/14/98
+	slopetype_t	slopetype;	// To aid move clipping.
+	sector_t	*frontsector, *backsector;
+	int 		validcount;	// if == validcount, already checked
+	int		locknumber;	// [Dusk] lock number for special
+};
+
+// phares 3/14/98
 //
 // Sector list node showing all sectors an object appears in.
 //