diff --git a/web/app/assets/javascripts/session_utils.js b/web/app/assets/javascripts/session_utils.js
index 3fc318fe2..725da855d 100644
--- a/web/app/assets/javascripts/session_utils.js
+++ b/web/app/assets/javascripts/session_utils.js
@@ -222,7 +222,16 @@
     rest.createJoinRequest(joinRequest)
       .done(function(response) {
 
-      }).error(context.JK.app.ajaxError);
+      }).error(function(jqXHR, textStatus, errorMessage) {
+          var joinErr = jqXHR.responseJSON['errors']
+          if (joinErr && joinErr['user_id'] == 'has already been taken') {
+              context.JK.app.notify({title: "Oops!", 
+                                     text: 'You have already requested to join this session.', 
+                                     "icon_url": "/assets/content/icon_alert_big.png"});
+          } else {
+              context.JK.app.ajaxError(jqXHR, textStatus, errorMessage);
+          }
+      });
 
     context.JK.app.layout.closeDialog('alert');
   }