//date validating
function check_date( date ) {
	if ( date.match(/^(\d{1,2})\/(\d{1,2})\/(\d{4})$/) ) {
		var dd = RegExp.$1;
		var mm = RegExp.$2;
		var yy = RegExp.$3;

		// try to create the same date using Date Object
		var dt = new Date(parseFloat(yy), parseFloat(mm)-1, parseFloat(dd), 0, 0, 0, 0);
		// invalid day
		if ( parseFloat(dd) != dt.getDate() ) { return false; }
		// invalid month
		if ( parseFloat(mm)-1 != dt.getMonth() ) { return false; }
		// invalid year
		if ( parseFloat(yy) != dt.getFullYear() ) { return false; }

		// everything fine
		return true;
	} else {
		// not even a proper date
		return false;
	}
};