Index: src/org/openstreetmap/josm/data/Preferences.java
===================================================================
--- src/org/openstreetmap/josm/data/Preferences.java	(revisione 3077)
+++ src/org/openstreetmap/josm/data/Preferences.java	(copia locale)
@@ -393,8 +393,16 @@
         File tmpFile = new File(prefFile + "_tmp");
         copyFile(tmpFile, prefFile);
         tmpFile.delete();
+
+        setCorrectPermissions();
     }
 
+    public void setCorrectPermissions() throws IOException {
+        // Make it owner-only-readable.
+        // FIXME: newest versions will use JDK 1.6, it has set*() functions.
+        Runtime.getRuntime().exec("/bin/chmod 600 " + getPreferenceFile().getAbsolutePath());
+    }
+
     /**
      * Simple file copy function that will overwrite the target file
      * Taken from http://www.rgagnon.com/javadetails/java-0064.html (CC-NC-BY-SA)
@@ -509,6 +517,13 @@
                 System.err.println(tr("Warning: Failed to initialize preferences.Failed to reset preference file to default: {0}", getPreferenceFile()));
             }
         }
+
+        try {
+            setCorrectPermissions();
+        }
+        catch (IOException e) {
+            e.printStackTrace();
+        }
     }
 
     public final void resetToDefault(){