1997 XJ8 3.2 V8 - Burning clutch then cut out - Restarted fine though ???

Hi everybody. Just last week I entered the world of Jag ownership, buy a '97 R-reg XJ8 with the 3.2 V8. It was cheap and I always fancied driving an older Jag, so dove in and bought this. 12 months MOT and seemed to drive pretty well considering mileage of 101k and its age. Only done about 70 miles in it so far but seemed ok....... until today......

Car had been parked outside the house in the baking sun all day. Went to get in it at 3pm and other than the steering wheel being so hot it burnt my hands, it was fine. Then half a mile down the road I noticed the distinct smell of burning clutch, although the car was driving fine. Jumped on the motorway and cruising at 70 and could still smell it after about 4 miles or so. Then all of a sudden the car died. Pulled in to the hard shoulder. Turned the ignition off and put it in Park, then turned ignition back on. Started the car and when it started it blew some smoke out the back but seemed to be running fine. Smoke cleared after 3 or 4 seconds. Gave throttle a blast and no more smoke. Continued my trip which was about another 4 miles or so and the car drove fine and there was no smell of burning clutch anymore......

Anybody got any ideas what on earth that was????

PS the temp gauge read fine all the time.