function send_reminder_form(){
   $fields=new Array();
   $fields[0]='remind_when';$fields[1]='remind_email';$fields[2]='event';
   ajax_post_form('inc/ajax/events_set_reminder.php',update_form,$fields);
}

function update_form(){ 
if (xmlHttp.readyState==4 || xmlHttp.readyState==200){ 
   document.getElementById('reminderform').innerHTML=xmlHttp.responseText;
} 
}