click event doesn't work in firefox

click event doesn't work in firefox

I've got such a code

  1.     $(document).ready(function () {
            $("td").click(function (e) {
                var child = $(e.target).attr("id");
                var td = $(this).find("span:first").text();
                var numberHolder = $(this).find("span:last").attr("id");
                var checkbox = $(this).find(".chbx input[type='checkbox']").attr("id");
                var clientBlockFlag;
                var indx;

                if ($("#" + checkbox).is(":checked")) {
                    indx = $("#<%=DropDownList_pastQuestions.ClientID%> option:selected").get(0).index;
                    clientBlockFlag = false;
                }
                else {
                    indx = $("#<%=DropDownList_pastQuestions.ClientID%> option:last-child").get(0).index;
                    clientBlockFlag = true;
                }

                //zmienna boolowska czy chbx is checked
                if (!(child.indexOf("chbx") >= 0)) {

                    if ($.trim(td) !== '') {
                        $.ajax({
                            type: "POST",
                            contentType: "application/json; charset=utf-3",
                            data: "{_word: '" + $.trim(td) + "', clientBlockFlag: '" + clientBlockFlag + "' }",
                            url: "bingo.aspx/getCellID",
                            dataType: "json",
                            success: function (msg) {
                                var anwser = msg.d;
                                if (!(anwser.indexOf("-1") >= 0)) {
                                    getID(anwser, td);
                                    $("#" + numberHolder).text(indx);
                                }
                            }
                        });
                    }
                  $("#" + checkbox).attr("checked", false);
                }
            });
        });








































My problem is click event works in Explorer and Chrome but not in Firefox. Can anybody tell me what i'm doing wrong?

Cheers,
Tomek