String.prototype.trim = function()
{
	return this.replace(/(^\s*)|(\s*$)/g,'');
}

function checkemail(email) {
    var re_deny = /(@.*@)|(\.\.)|(^\.)|(^@)|(@$)|(\.$)|(@\.)/;
    var re_dn = /^.+\@[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,4}$/;
    var re_ip = /^.+\@\[(((1?[0-9])?[0-9])|(2[0-4][0-9])|(25[0-5]))(\.(((1?[0-9])?[0-9])|(2[0-4][0-9])|(25[0-5]))){3}\]$/;
    return( ! re_deny.test(email) && ( re_dn.test(email) || re_ip.test(email) ) );
}

function date_check( date ) {
    ymd = date.split( "-" );
    if( ymd.length != 3 ) {
	return false;
    }
    jsdate = new Date( Number(ymd[0]), Number(ymd[1]-1), Number(ymd[2]) );
    lim = new Date( 1970, 0, 1 );
    if( jsdate < lim ) {
	return false;
    }
    lim = new Date( 2038, 0, 19 );
    if( jsdate > lim ) {
        return false;
    }
    y = "0000" + jsdate.getFullYear();
    m = "00" + ( jsdate.getMonth() + 1 );
    d = "00" + jsdate.getDate();
    return date == y.substr(y.length-4,4) + "-" + m.substr(m.length-2,2) + "-" + d.substr(d.length-2,2);
}