message: issue#306: crash fix
diff: @@ -179,7 +179,7 @@ OP_NAMESPACE_BEGIN
  iter->Next();
  }
  DELETE(iter);
  - if (need_set_minmax)
  + if (need_set_minmax && reply.MemberSize() > 0)
  {
  new_meta.SetObjectLen(reply.MemberSize());
  new_meta.GetMin().SetString(reply.MemberAt(0).str, true);
  