--- /Metaphone.java	2023-07-05 03:04:22.666041701 +0200
+++ /Codec-1/src/java/org/apache/commons/codec/language/Metaphone.java	2023-07-05 03:04:22.666041701 +0200
@@ -85,7 +85,7 @@
         }
         // single character is itself
         if (txt.length() == 1) {
-            return txt.toUpperCase(java.util.Locale.ENGLISH) ;
+return txt.toUpperCase ( null )  ;
         }
       
         char[] inwd = txt.toUpperCase(java.util.Locale.ENGLISH).toCharArray() ;
