KO ObservableArray update breaks when binding with .sort

KO ObservableArray update breaks when binding with .sort

I'm sorting my ObservableArray in the markup thusly, but for some reason,
when I push a new object to the pages ObservableArray, this does not
update.
//store.get('pages') returns an ObservableArray
<!-- ko foreach:store.get('pages').sort(function (l , r ) { return
l.pageNumber() < r.pageNumber() ? -1 : 1}) -->
<markup/>
<!--/ko-->
However, when I remove the sort call, it catches the array change just
fine. Like so,
//works fine, updates when item pushed to observableArray
<!-- ko foreach:store.get('pages') -->
<markup/>
<!--/ko-->
Any idea for a simple workaround?
Edits:
Tried using valueHasMutated(), doesn't force an update either.