diff --git a/Source/objects.cpp b/Source/objects.cpp
index d60b220b5..5651a404a 100644
--- a/Source/objects.cpp
+++ b/Source/objects.cpp
@@ -809,10 +809,12 @@ void __fastcall AddL3Objs(int x1, int y1, int x2, int y2)
 	}
 }
 
-BOOLEAN __fastcall WallTrapLocOk(int xp, int yp)
+BOOL __fastcall WallTrapLocOk(int xp, int yp)
 {
-	return (~dFlags[xp][yp] & DFLAG_POPULATED) >> 3;
-}
+	if (dFlags[xp][yp] & DFLAG_POPULATED)
+		return FALSE;
+	return TRUE;
+} 
 
 void __cdecl AddL2Torches()
 {
diff --git a/Source/objects.h b/Source/objects.h
index 66ee7b950..cad0f5a13 100644
--- a/Source/objects.h
+++ b/Source/objects.h
@@ -28,7 +28,7 @@ void __cdecl InitRndBarrels();
 void __fastcall AddL1Objs(int x1, int y1, int x2, int y2);
 void __fastcall AddL2Objs(int x1, int y1, int x2, int y2);
 void __fastcall AddL3Objs(int x1, int y1, int x2, int y2);
-BOOLEAN __fastcall WallTrapLocOk(int xp, int yp);
+BOOL __fastcall WallTrapLocOk(int xp, int yp);
 void __cdecl AddL2Torches();
 BOOL __fastcall TorchLocOK(int xp, int yp);
 void __cdecl AddObjTraps();