Line 16 of jmx.php currently is set as below
if (isset($_GET['change_mx4j_node'])) $_SESSION['mx4j_node'] = $_GET['mx4j_node'];
But observing the logic below line 16, the correct _GET paramenter setting _SESSION[mx4j_node] should be change_mx4j_node instead of mx4j_node
Making that line
if (isset($_GET['change_mx4j_node'])) $_SESSION['mx4j_node'] = $_GET['change_mx4j_node'];
Line 16 of jmx.php currently is set as below if (isset($_GET['change_mx4j_node'])) $_SESSION['mx4j_node'] = $_GET['mx4j_node'];
But observing the logic below line 16, the correct _GET paramenter setting _SESSION[mx4j_node] should be change_mx4j_node instead of mx4j_node Making that line
if (isset($_GET['change_mx4j_node'])) $_SESSION['mx4j_node'] = $_GET['change_mx4j_node'];