--- old/agent/src/share/classes/sun/jvm/hotspot/oops/java_lang_Class.java	Fri Sep  9 11:55:31 2011
+++ new/agent/src/share/classes/sun/jvm/hotspot/oops/java_lang_Class.java	Fri Sep  9 11:55:30 2011
@@ -55,13 +55,13 @@
     // klass and oop_size are HotSpot magic fields and hence we can't
     // find them from InstanceKlass for java.lang.Class.
     Type jlc = db.lookupType("java_lang_Class");
-    int klassOffset = (int) jlc.getCIntegerField("klass_offset").getValue();
+    int klassOffset = (int) jlc.getCIntegerField("_klass_offset").getValue();
     if (VM.getVM().isCompressedOopsEnabled()) {
       klassField = new NarrowOopField(new NamedFieldIdentifier("klass"), klassOffset, true);
     } else {
       klassField = new OopField(new NamedFieldIdentifier("klass"), klassOffset, true);
     }
-    int oopSizeOffset = (int) jlc.getCIntegerField("oop_size_offset").getValue();
+    int oopSizeOffset = (int) jlc.getCIntegerField("_oop_size_offset").getValue();
     oopSizeField = new IntField(new NamedFieldIdentifier("oop_size"), oopSizeOffset, true);
   }