It's worth mentioning that SortedSet and SortedMap implementations already exist and were added in May 2011. This means when these collection types are used and the @Sort annotation or its successor annotations, @SortComparator or @SortNatural are applied, the collections are properly sorted. We have test cases for @ManyToMany assocations which use @Sort but no tests which use the more recently added @SortComparator and @SortNatural annotations. I'll be sure to add test cases for those annotations specifically, but the code to support them is already in place.