Error calling webservice using JSONP + jquery with IE on remote domain

I have a .Net webservice on my app server that returns data formatted as JSONP. I have an HTML test client on that server which works fine using IE, Firefox, & Chrome. If I copy the same HTML to my workstation or deploy to my webserver it works with Firefox & Chrome but in IE I'm getting two javascript errors.

Message: Object doesn't support this property or method

Line: 1

Char: 1

Code: 0

URI: http://mydomain/WebServices/LyrisProxy/Services/Lyris/JSONP/Lyris.asmx/AddUser?lyrisInstance="1"&email="myemail@gmail.com"&fullName="My Name"&lyrisList="l开发者_如何转开发istname"&format=json&callback=jsonp1274109819864&_=1274109829665

Message: Member not found.

Line: 59

Char: 209

Code: 0

URI: http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js

I'm kind of at loss as to what to do to fix this.

Here's my javascript. It's actually not the JSONP causing the error but rather the call to jqModal ev.preventDefault();. I'm trying to go through this now to see why it bombs with an external reference to that on IE.

<script type="text/javascript">
    $(document).ready(function() {
        $("#createUser").live("click", function(ev) {
            var invalidEmailAddressMessage = "That isn't a valid email address.";
            var userSuccessfullyAddedMessage = "Congrats! You've been added to the iStage mailing list.";
            var userAlreadyExistsMessage = "Looks like you're already on our mailing list!";
            var genericErrorMessage = "Something fishy happened. I don’t know what to tell you.";

            // check for a valid email address
            var regEmail = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
            if(regEmail.test($("#email").val()) == false) {
                // invalid email address. Show error and let user retry.
                ev.preventDefault();
                $('#lyrisReturnStatus').jqmShow().oneTime(3500, "soon", function() {
                    $('#lyrisReturnStatus').jqmHide();
        });
        $("#output").html(invalidEmailAddressMessage);
        $("#email").select();
        return;
            }

            // Call the proxy to add the user
            var service = new WS("http://apps.ce.org/WebServices/LyrisProxy/Services/Lyris/JSONP/Lyris.asmx", WSDataType.jsonp);
            service.call("AddUser", { lyrisInstance:$("#lyrisInstance").val(), email:$("#email").val(), fullName:$("#fullName").val(), lyrisList:$("#lyrisList").val() }, function(AddUser) {
                var lyrisReturn = JSON.parse(AddUser);
                var goBack;
                var timeout;

                // See if the JSON returned is an error message and handle.
                if(typeof(lyrisReturn.ErrorMessage) !== 'undefined' && lyrisReturn.ErrorMessage != null) {
                    var pos=lyrisReturn.ErrorMessage.indexOf("member already exists");
                    if (pos>=0)
                    {
                        // Member already exists.
                        $("#output").html(userAlreadyExistsMessage);
                        goBack = true;
                    } else {
                        // Generic error.
                        $("#output").html(genericErrorMessage);
                        goBack = false;
                    }
                    timeout = 3500;
                }
                // See if the JSON returned the expected MemberID
                if(typeof(lyrisReturn.MemberID) !== 'undefined' && lyrisReturn.MemberID != null) {
                    $("#output").html(userSuccessfullyAddedMessage);
                    goBack = true;
                    timeout = 2000;
                }

                //Show the modal display with the appropriate messaging and redirect.
                ev.preventDefault();
                $('#lyrisReturnStatus').jqmShow().oneTime(timeout, "soon", function() {
                    $('#lyrisReturnStatus').jqmHide();
                    if(goBack) {
             history.go(-1);
         }
    });

            });
        });
        $('#lyrisReturnStatus').
          jqm({ overlay: 50, modal: true, trigger: false });
    });
</script>

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