function pairstr2Arr ($str) {
    $elems = explode(',', $str);
    foreach( $elems as $elem => $val ) {
        $val = trim($val);
        $arr[] = explode('=', $val);
        $arr[$elem][0] = trim($arr[$elem][0]);
        $arr[$elem][1] = trim($arr[$elem][1]);
    }
    return $arr;
}