function FillDays(nYear, nMonth, oDaysSelect) {
    var nDays;
    switch (nMonth) {
        case 1: case 3: case 5: case 7: case 8: case 10: case 12:
            nDays = 31;
            break;
        case 4: case 6: case 9: case 11:
            nDays = 30;
            break;
        case 2:
            if ((nYear % 4) != 0) {
                nDays = 28;
            }
            else {
                nDays = 29;
            }
            break;
    }
    
    var nDay = oDaysSelect.selectedIndex;
    
    while (oDaysSelect.hasChildNodes())
        oDaysSelect.removeChild(oDaysSelect.childNodes[0]);
        
    for (var i = 1; i <= nDays; i++) {
        var oOption = document.createElement('option');
        oOption.appendChild(document.createTextNode(i.toString()));
        oOption.setAttribute('value', i.toString());
        if (nDay == i - 1){
            oOption.setAttribute('selected', 'true');
        }
        oDaysSelect.appendChild(oOption);
    }
}
function FillYears(oYearsSelect, nStartyear, nEndyear) {
    for (var i = nEndyear; i >= nStartyear; i--) {
        var oOption = document.createElement('option');
        oOption.appendChild(document.createTextNode(i.toString()));
        oOption.setAttribute('value', i.toString());
        oYearsSelect.appendChild(oOption);
    }
}