diff -r a6ac0a32d3ea -r 2dcc8f2e1a1b emul/src/main/java/java/lang/StringBuilder.java
--- a/emul/src/main/java/java/lang/StringBuilder.java	Sun Sep 30 17:29:51 2012 -0700
+++ b/emul/src/main/java/java/lang/StringBuilder.java	Thu Jan 03 11:11:30 2013 +0100
@@ -376,8 +376,7 @@
      * @throws NullPointerException {@inheritDoc}
      */
     public int indexOf(String str, int fromIndex) {
-        return String.indexOf(value, 0, count,
-                              str.toCharArray(), 0, str.length(), fromIndex);
+        return super.indexOf(str, fromIndex);
     }
 
     /**