I have basically this on a page:

<script type="text/javascript">
function refresh_context() {
    $("#ajax-context").html("Searching...");
    $.get("/ajax/ldap_search.php", {cn: $("#username").val()}, function(xml) {
        $("#ajax-context").html($("display", xml).text());
        $("#context").val($("context", xml).text());
    }, 'xml');
}
$(document).ready(function() {
    $("#username").blur(refresh_context);
});
</script>

<input type="text" name="username" id="username" maxlength="255" value="" />
<input type="hidden" name="context" id="context" value=""/>
<div id="ajax-context"></div>

What it should do (and does fine on Firefox) is when you type a username in to the #username field, it will run /ajax/ldap_search.php?cn=$username, which searches our company's ldap for the username and returns it's raw context and a formatted version of the context like this:

<result>
    <display>Staff -&gt; Accounting -&gt; John Smith</display>
    <context>cn=jsmith,ou=Accounting,ou=Staff,ou=Users,o=MyOrg</context>
</result>

The formatted version (display) goes to the div #ajax-context and goes to the hidden input #context. (Also, the -> are actually - "& g t ;" (without spaces)).

However, on IE the div stays stuck on "Searching..." and the hidden input value stays blank.

I've tried both .get and .post and neither work. I'm sure it's failing on the .get because if I try this, I don't even get the alert:

$.get("/ajax/ldap_search.php", {cn: $("#username").val()}, function() {
    alert("Check");
});

Also, IE doesn't give me any script errors.

Edit: Added "$(document).ready(function() {", the .blur was already in it in my code, but I forgot to include that in my post.

Edit 2: The request is being sent and apache2 is receiving it:

10.135.128.96 - - [01/May/2009:10:04:27 -0500] "GET /ajax/ldap_search.php?cn=i_typed_this_in_IE HTTP/1.1" 200 69