It worked out nicely, easily and quickly.
(1) I got the buyer to agree that the negative feedback was a misunderstanding, not warranted, and that he would change it.
(2) I had eBay mail him the appropriate Feedback Revision form: http://pages.ebay.com/help/feedback/revision-request.html
(3) He checked OK and returned the form to eBay.

Robert
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Isabelle Adjani in "The Driver" (1978).
http://www.antiquegamblingchips.com/StillsC_FemaleStars.htm