draggable() and droppable() not functioning in IE6,7

Question

hallo everyone, the drag and drop app that i have built functions perfectly in chrome and firefox but when i try it on IE i get "Object required" as error . so the draggable() does not work at all. can anyone please help me solve this bug.thanks

function readJSON(json, i, end) {
    myarray = eval(json);
    $.each(myarray, function (index, value) {
        if (i <= end && i == index) {
            var $str = value.split('<br/>');

            var $tooltip = $('<span></span>').html($str[0]).addClass('tooltiphidden');
            var $newDiv = $('<div id =\"' + $str[3] + '\"></div>').addClass('items').html($str[1] + '&nbsp;&nbsp;' + $str[2]);
            $newDiv.append($tooltip);

            $newDiv.mousedown(function () {
                $newDiv.contents("span:last-child").css({
                    display: "none"
                });
                moveditem = $str[0] + '<br/>' + $str[2];
            }).draggable({
                helper: 'clone',
                opacity: 0.5
            });
            $('div.selectedItemlist').droppable({
                accept: 'div.items',
                drop: function (e, ui) {
                    $newSelectedItem = $('<div id=\"' + ui.draggable.attr('id') + '\"></div>').html(ui.draggable.html()).addClass('dropitems');
                    $tooltip = $('<span></span>').html(moveditem).addClass('tooltiphidden');
                    $('input#inrs').val($('#inrs').val() + ui.draggable.attr('id') + ',');
                    $('div.selectedItemlist').append($newSelectedItem);
                    ui.draggable.remove();
                    $('div.selectedItemlist').css({
                        backgroundColor: 'white',
                        opacity: 1
                    });
                },
                over: function (e, ui) {
                    $('div.selectedItemlist').css({
                        backgroundColor: 'red',
                        opacity: 0.2
                    });
                },
                out: function (e, ui) {
                    $('div.selectedItemlist').css({
                        backgroundColor: 'white',
                        opacity: 1
                    });
                }
            });
            $newDiv.appendTo('div.suggestions');

            i++;
        }
    });
}