I would say, i.e. that the users (using term also to include whichever group or entity ordered/requested the software) are satisfied that it meets their requirements.

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Note added at 8 mins (2007-04-13 16:46:59 GMT)
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note too that in IT, "recette" is also the equivalent of "user acceptance (testing), not unrelated to Jock's 'validation' in his answer, but not the term used.