A key issue in open multiagent systems is that of solving the difficulty of an agent to understand messages coming from other agents having different ontologies.
is a new way of facing this issue, by exploiting techniques that allow the agents of a MAS to reach mutually acceptable agreements on the exchanged terms. The produced scenario is similar to that of human discussions, where human beings try to solve those situations in which the involved terms are not mutually understandable, by
the semantics of these terms. The HISENE approach is a recent JADE-based protocol effectively supporting semantic negotiation. It is based on the idea that an agent that does not understand a term can automatically require the help of other agents that it considers particularly reliable. However, HISENE does not take in account either the possibility of wrong answers coming from the requested agents or the fact that a term can have different meanings. In order to cover these two important issues, in this paper we present an extension of HISENE, called HISENE2, and we show experimentally that it performs better than HISENE with respect both to the quality and the efficiency of the semantic negotiation.