Index: trunk/src/org/openstreetmap/josm/data/CustomConfigurator.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/CustomConfigurator.java	(revision 9522)
+++ trunk/src/org/openstreetmap/josm/data/CustomConfigurator.java	(revision 9524)
@@ -97,4 +97,16 @@
     }
 
+    /**
+     * Resets the log.
+     */
+    public static void resetLog() {
+        summary = new StringBuilder();
+    }
+
+    /**
+     * Read configuration script from XML file, modifying main preferences
+     * @param dir - directory
+     * @param fileName - XML file name
+     */
     public static void readXML(String dir, String fileName) {
         readXML(new File(dir, fileName));
@@ -474,6 +486,6 @@
             try {
                 this.mainPrefs = mainPrefs;
-                summary = new StringBuilder();
-                engine = new ScriptEngineManager().getEngineByName("rhino");
+                resetLog();
+                engine = new ScriptEngineManager().getEngineByName("JavaScript");
                 engine.eval("API={}; API.pref={}; API.fragments={};");
 
@@ -493,4 +505,5 @@
             } catch (Exception ex) {
                 log("Error: initializing script engine: "+ex.getMessage());
+                Main.error(ex);
             }
         }