Phone mask with jQuery and Masked Input Plugin

Try this – http://jsfiddle.net/dKRGE/3/

$("#phone").mask("(99) 9999?9-9999");

$("#phone").on("blur", function() {
    var last = $(this).val().substr( $(this).val().indexOf("-") + 1 );

    if( last.length == 3 ) {
        var move = $(this).val().substr( $(this).val().indexOf("-") - 1, 1 );
        var lastfour = move + last;
        var first = $(this).val().substr( 0, 9 );

        $(this).val( first + '-' + lastfour );
    }
});