In order to perform effective communication agents must be able to foresee the effects of their utterances on the addressee’s mental state. In this paper we investigate the update of the mental state of a hearer agent as a consequence of the utterance performed by a speaker agent. Given an agent communication language with a STRIPS-like semantics, we propose a set of criteria that allow the binding of the speaker’s mental state to its uttering of a certain sentence. On the basis of these criteria, we give an abductive procedure that the hearer can adopt to partially recognize the speaker’s mental state, on the basis of its utterances. This procedure can be adopted by the hearer to update its own mental state and its image of the speaker’s mental state.