--- a/hotspot/src/share/vm/oops/instanceKlass.cpp	Wed Oct 23 10:24:28 2013 +0200
+++ b/hotspot/src/share/vm/oops/instanceKlass.cpp	Thu Oct 24 10:02:02 2013 +0200
@@ -2393,15 +2393,38 @@
 
 
 const char* InstanceKlass::signature_name() const {
+  int hash_len = 0;
+  char hash_buf[40];
+
+  // If this is an anonymous class, append a hash to make the name unique
+  if (is_anonymous()) {
+    assert(EnableInvokeDynamic, "EnableInvokeDynamic was not set.");
+    intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
+    sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
+    hash_len = (int)strlen(hash_buf);
+  }
+
+  // Get the internal name as a c string
   const char* src = (const char*) (name()->as_C_string());
   const int src_length = (int)strlen(src);
-  char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
-  int src_index = 0;
+
+  char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
+
+  // Add L as type indicator
   int dest_index = 0;
   dest[dest_index++] = 'L';
-  while (src_index < src_length) {
+
+  // Add the actual class name
+  for (int src_index = 0; src_index < src_length; ) {
     dest[dest_index++] = src[src_index++];
   }
+
+  // If we have a hash, append it
+  for (int hash_index = 0; hash_index < hash_len; ) {
+    dest[dest_index++] = hash_buf[hash_index++];
+  }
+
+  // Add the semicolon and the NULL
   dest[dest_index++] = ';';
   dest[dest_index] = '\0';
   return dest;