--- a/pytask/static/js/login.js	Tue Jan 18 14:34:26 2011 +0530
+++ b/pytask/static/js/login.js	Tue Jan 18 14:37:06 2011 +0530
@@ -1,17 +1,42 @@
 var login_user = function (login_url) {
+
+  /* Function that handles the post login request changes. */
+  var process_login_response = function (raw_data) {
+    /* We expect an exception when login fails. Read comment with catch. */
+    try {
+      data = $.parseJSON(raw_data);
+      if (data.authentication == "success") {
+        /* Login succeeded */
+        if (data.markup) {
+          /* Replace the HTML with the user actions since
+           * the request came from a URL other than logout page */
+          $("div#useraction").replaceWith(data.markup);
+        } else if (data.redirect) {
+          /* Reload the page to the pytask home page since
+           * the login request came from logout page. This
+           * is done because the logout text says you have
+           * been logged out, which will be awkward after
+           * user re-logs in. */
+          window.location.href=data.redirect;
+        }
+      }
+    } catch (e) {
+      /* Login failed so the login view returned to the same view as
+       * the existing page from which the call was made and thus we
+       * get html. So let us display the error. */
+      $('div #loginform #error').show();
+    }
+  }
+
+
+  /* Attach a handler which does the form post upon the submit
+   * button is pressed on the login form. */
   $(document).ready(function () {
     $('#form_login').submit(function() {
       $.post(
         login_url,
         $("#form_login").serialize(),
-        function (raw_data) {
-          data = $.parseJSON(raw_data);
-          alert(data);
-          if (data.authentication == "success") {
-            $("div#useraction").replaceWith(data.markup);
-            alert(data.markup);
-          }
-        });
+        process_login_response);
       return false;
     });
   });