Jquery functions to check all and uncheck header

I have a page with repeater in it. The repeater header contains a checkbox and all rows contains  check boxes.

CodeProject




CodeProject

I want to select the all the check boxes when i click on the header check box. and i want to remove the headec check, if i uncheck any checkbox.
here is the code.

  function UncheckHeader(header) {
        $('#divVOIUserPool input:checkbox').each(function() {
            if (!$(this).is(':checked')) {              
                $('#' + header).removeAttr('checked');
            }
        });
    }

    function CheckAll(checkbox) {
        $('#divVOIUserPool input:checkbox').each(function() {
            if (!$(this).is(':disabled')) {
                this.checked = checkbox.checked;
            }
        });
    }

Simple i ve put one div as outer to the repeater and named it as 'divVOIUserPoo', and added the properties in repeater item bound. like.

 chkSelectValue.Attributes.Add("onClick", "javascript:UncheckHeader('" + ViewState["chkHeaderSelect"].ToString() + "');");  -- for row check boxes in item and alternative item and for header its like--
ViewState["chkHeaderSelect"] = chkHeaderSelect.ClientID;
                    chkHeaderSelect.Attributes.Add("onClick", "javascript:CheckAll(this);");
in the header of the item bound