Why doesnt this work?

Why doesnt this work?

Im trying too animate using opacity. This code broke after updating to Jquery 1.4.
Im using this code:
function fadeTitles() {
$(".line_inner").load("/ajax/shouts.php").fadeIn(3400).animate({opacity: "1.0"}, 3400).fadeOut("slow", function() {setTimeout(this, 3400);});
setTimeout('fadeTitles();', 3400);
}
// Document ready
$(document).ready(function() {
fadeTitles();
}