--- a/src/newgrf.cpp	Thu Mar 27 16:09:15 2008 +0000
+++ b/src/newgrf.cpp	Thu Mar 27 17:06:35 2008 +0000
@@ -3555,6 +3555,10 @@
 			return true;
 		}
 
+		case 0x22: // difficulty level
+			*value = _opt.diff_level;
+			return true;
+
 		default: return false;
 	}
 }