diff --git a/src/compatibility.cpp b/src/compatibility.cpp
index e7121da8b..ae3b905d0 100644
--- a/src/compatibility.cpp
+++ b/src/compatibility.cpp
@@ -555,7 +555,14 @@ void SetCompatibilityParams()
 					if ((unsigned)CompatParams[i + 1] < (unsigned)numsectors)
 					{
 						// this assumes that the sector does not have any tags yet!
-						tagManager.AddSectorTag(CompatParams[i + 1],  CompatParams[i + 2]);
+						if (CompatParams[i + 2] == 0)
+						{
+							tagManager.RemoveSectorTags(CompatParams[i + 1]);
+						}
+						else
+						{
+							tagManager.AddSectorTag(CompatParams[i + 1], CompatParams[i + 2]);
+						}
 					}
 					i += 3;
 					break;
diff --git a/wadsrc/static/compatibility.txt b/wadsrc/static/compatibility.txt
index d796db843..61d13b6df 100644
--- a/wadsrc/static/compatibility.txt
+++ b/wadsrc/static/compatibility.txt
@@ -53,7 +53,11 @@ A80E7EE40E0D0C76A6FBD242BE29FE27 // map15
 
 5C594C67CF7721005DE71429F9811370 // Eternal Doom map03
 {
-	stairs
+	// fix broken staircase. The compatibility option is not sufficient
+	// to reliably handle this so clear the tags from the unwanted sectors.
+	setsectortag 212 0
+	setsectortag 213 0
+	setsectortag 214 0
 }
 
 6DA6FCBA8089161BDEC6A1D3F6C8D60F // Eternal Doom MAP25