We present an experiment where subjects were asked to listen to Swedish human-computer dialogue fragments where a synthetic voice makes an elliptical clarification after a user turn. The prosodic features of the synthetic voice were systematically varied, and subjects were asked to judge the computer's actual intention. The results show that an early low F0 peak signals acceptance, that a late high peak is perceived as a request for clarification of what was said, and that a mid high peak is perceived as a request for clarification of the meaning of what was said. The study can be seen as the beginnings of a tentative model for intonation of clarification ellipses in Swedish, which can be implemented and tested in spoken dialogue systems.