diff --git a/oauth3.core.js b/oauth3.core.js
index bee3d67..e44cc94 100644
--- a/oauth3.core.js
+++ b/oauth3.core.js
@@ -16,9 +16,15 @@
     var qs = [];
 
     Object.keys(params).forEach(function (key) {
+      // TODO nullify instead?
+      if ('undefined' === typeof params[key]) {
+        return;
+      }
+
       if ('scope' === key) {
         params[key] = core.stringifyscope(params[key]);
       }
+
       qs.push(encodeURIComponent(key) + '=' + encodeURIComponent(params[key]));
     });
 
@@ -182,6 +188,10 @@
     var clientId = opts.appId || opts.clientId;
 
     var args = directive.otp;
+    if (!directive.otp) {
+      console.log('[debug] loginCode directive:');
+      console.log(directive);
+    }
     var params = {
       "username": opts.id || opts.username
     , "request_otp": true // opts.requestOtp || undefined