problem with jQuery datepicker

problem with jQuery datepicker

Hi!
Please help me with one thing. I'm using jquery UI datepicker on my page in this way:
var list = {};
        function getEventsDatesList() {
            // fill list with dates to be display in calendar
            ...
            list[new Date(date[2], date[0] - 1, date[1])] = true;
        }

        $j(document).ready(function() {
            getEventsDatesList();

            var lblMonthName = $j("#lblMonthName");
            var arrMonthNames = ['....']; //monthes names

            $j("#calendar").datepicker({
                changeMonth: false,
                changeYear: false,
                minDate: new Date(2009, 4 - 1, 1),
                maxDate: new Date(2009, 12 - 1, 31),
                onSelect: function(dateText) {
                    window.location = "Restaurants-List.aspx?date=" + (dateText.replace('.', '-').replace('.', '-'));
                },
                beforeShowDay: function(date) {
                    //console.log([date, list[date]]);
                    return [list[date], 'event'];
                },
                onChangeMonthYear: function(year, month, inst) {
                    lblMonthName.html(arrMonthNames[month - 1]);
                },
                monthNames: arrMonthNames,
                dateFormat: 'dd.mm.yy',
                firstDay: 1
            });
        });

I'm using beforeShowDay event to make enabled only dates which are in the list variable;
But this not works on the page load. When I change monthes in the datepicker it begins to work fine. Why it doesn't work on the first load?
Thanks in advance!