Stop a jQueryUI effect

Stop a jQueryUI effect

I'm developing a kind of chat similar the Facebook one. I used the jQuery
UI highlight effect when a new message arrives. Now I want to stop this
effect when the user click on the windows.
This is my code on window click event. The "janela" class is the chat's
windows.
$('.janela').live('click', function(){
var id = $(this).children('.topo').attr('id');
$.post('sys/chat.php',{acao: 'mudar_status', user: id});
$(".topo").effect("none"); //it's just a frustrated try.
});
Thanks.