diff --git a/lib/javascript-static.js b/lib/javascript-static.js
index a5f3194b0f2..1d9b0915ecf 100644
--- a/lib/javascript-static.js
+++ b/lib/javascript-static.js
@@ -89,6 +89,9 @@ function lockoptionsall(formid) {
     var tolock = Array();
     for (var dependon in dependons) {
         var master = form[dependon];
+        if (master == undefined) {
+            continue;
+        }
         for (var condition in dependons[dependon]) {
             for (var value in dependons[dependon][condition]) {
                 var lock;
@@ -118,6 +121,9 @@ function lockoptionsall(formid) {
     }
     for (var el in tolock){
         var formelement = form[el];
+        if (formelement == undefined) {
+            continue;
+        }
         formelement.disabled = tolock[el];
     }
     return true;
@@ -128,6 +134,9 @@ function lockoptionsallsetup(formid) {
     var dependons = eval(formid+'items');
     for (var dependon in dependons) {
         var master = form[dependon];
+        if (master == undefined) {
+            continue;
+        }
         master.onclick  = function() {return lockoptionsall(this.form.getAttribute('id'));};
         master.onblur   = function() {return lockoptionsall(this.form.getAttribute('id'));};
         master.onchange = function() {return lockoptionsall(this.form.getAttribute('id'));};