This paper focuses on the " oui " / " yes " feedback produced by a patient in the specific medical environment of breaking bad news. In particular, we aim at determining the role of prosody (intonation and temporal delay with which " oui " is produced) in the perception of this feedback. 15 French listeners listened to short human-human interactions between an acting doctor and his patient. They judged the more or less appropriate nature of the " oui " produced by the patient, based on the way it was orally said. The effects of intonation (neutral/ shaken/questioning), delay (short/long), and listener sex (male/female) on judgment scores (1-5) and on the log of reaction times were measured. The results show a role of intonation and delay in a specific part (" phase ") of the dialogue (Problem Definition) with female and male listeners being sensitive to different aspects of prosody. This has implications for modeling prosody of a virtual patient's feedbacks in the context of humane-machine interaction.