The algorithm used on AMQ quorum vote has a bug that can make it to declare a successfull quorum votation depending by the order of negative "request to stay live" vote results.

For example: in a 5 nodes cluster the quorum can be achieved with 3 positive votes and if the broker requesting the quorum vote will receive first 1 negative vote and 2 positive ones (or 2 negatives and 1 positive one) it will declare the quorum vote complete and successfull, while it shouldn't.