diff --git a/macros.h b/macros.h
index acf6a6c6bd..7d886fbe0b 100644
--- a/macros.h
+++ b/macros.h
@@ -167,7 +167,11 @@ static inline void swap_tile(TileIndex *a, TileIndex *b) { TileIndex t = *a; *a
 /* IS_INT_INSIDE = filter for ascii-function codes like BELL and so on [we need an special filter here later] */
 static inline bool IsValidAsciiChar(byte key)
 {
-	return IS_INT_INSIDE(key, ' ', 256);
+	// XXX This filter stops certain crashes, but may be too restrictive.
+	return IS_INT_INSIDE(key, ' ', 127) ||
+		(IS_INT_INSIDE(key, 160, 256) &&
+		key != 0xAA && key != 0xAC && key != 0xAD && key != 0xAF &&
+		key != 0xB5 && key != 0xB6 && key != 0xB7 && key != 0xB9);
 }
 
 #endif /* MACROS_H */