I'd like to find out whether my reply got downvoted by the same person who upvoted it. As I'm relatively new to ServerFault I'd like to ask the voter to clarify what it is they think I should or should not be doing.

Background: I answered a question at https://serverfault.com/questions/189720/stun-server-for-windows/190115 The answer I provided had already been mentioned in a comment. My answer credited the person who made that comment. I provided an answer (as an answer, not a comment) so that the question could eventually disappear from the list of outstanding questions - thus making it easier to browse unanswered questions. Should I just have contacted the commenter to suggest they themselves re-enter their comment as an answer? Is there a mechanism for this? Whats's the local etiquette for this situation?