Telephoto Woes

Unfortunately my telephoto lens has thrown its toys in a most alarming way (this photo of Tony in his kayak was one of the last). I think it must be something to do with the lens/camera body interface - aperture settings cycle randomly between f9 and f96, the focus motor refuses to budge, and basically the whole thing has become a bit of a useless lump. I'll try to get hold of Sigma's repair agent in New Zealand, and see what has to be done.