/**
* show / hides numbered form fields leaving only given num displayed
*/
function ShowHideNumberedFormFields(jqObj, nameprefix, num) {
    var max = 100;
    var i = 1;

    while (jqObj("textarea[@name='"+nameprefix+i+"']").length) {
        if (i>num)
            jqObj("textarea[@name='"+nameprefix+i+"']").parent().parent().hide();
        else
            jqObj("textarea[@name='"+nameprefix+i+"']").parent().parent().show();

        if (++i > max)
            return false;
    }
}