function calendar_redirect()
{
    var date = document.JSCalendar.c_startdate.value;
    var url = window.location.href;
    var seperator;
    
    if(url.indexOf("?") > 0) seperator = "&";
    else seperator = "?";
    if(url.indexOf("category") > 0) window.location.href = url + seperator + 'startdate=' + date;
    else window.location.href = 'http://www.frankentipps.de/?startdate=' + date;
}