Index: trunk/src/org/openstreetmap/josm/tools/XmlObjectParser.java
===================================================================
--- trunk/src/org/openstreetmap/josm/tools/XmlObjectParser.java	(revision 5509)
+++ trunk/src/org/openstreetmap/josm/tools/XmlObjectParser.java	(revision 5510)
@@ -12,4 +12,5 @@
 import java.util.Iterator;
 import java.util.LinkedList;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Stack;
@@ -189,7 +190,7 @@
                     if (fieldName.startsWith(lang)) {
                         int l = lang.length();
-                        fieldName = "set" + fieldName.substring(l, l + 1).toUpperCase() + fieldName.substring(l + 1);
+                        fieldName = "set" + fieldName.substring(l, l + 1).toUpperCase(Locale.ENGLISH) + fieldName.substring(l + 1);
                     } else {
-                        fieldName = "set" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1);
+                        fieldName = "set" + fieldName.substring(0, 1).toUpperCase(Locale.ENGLISH) + fieldName.substring(1);
                     }
                     Method m = entry.getMethod(fieldName);