I'm trying the examples from http://docs.jquery.com/Tutorials:Getting_Started_with_jQuery and found that the AJAX post function does now work:

     $.post("rate.php", {rating: $(this).html()}, function(xml) {
       // format and output result
       $("#rating").html(
         "Thanks for rating, current average: " +
         $("average", xml).text() +
         ", number of votes: " +
         $("count", xml).text()
       );
     });

As I can see in FireBug, it does an OPTIONS call instead of a POST call.

It works fine in previous versions. It affect jQuery 1.5 only.

OS: Kubuntu 10.04

Browsers: FF 3.6.13, Opera 11.01, Google Chrome 5.0.375.126,

(I haven't tried on IE)