Event.observe(window, 'load', start);

function start()
{
	check_msgs();
	//var interval_id = setInterval("check_msgs()",30000)
}
function check_msgs()
{
	new Ajax.PeriodicalUpdater('msgs', '/check_msgs.php', { // Changed to Ajax.PeriodicalUpdater
	    asynchronous:true,
            method:'get',
            frequency:30
        });

}