diff --git a/core/includes/common.inc b/core/includes/common.inc
index a4fcf51..c69dfbe 100644
--- a/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -855,7 +855,7 @@ function drupal_http_request($url, array $options = array()) {
 
   // If the server URL has a user then attempt to use basic authentication.
   if (isset($uri['user'])) {
-    $options['headers']['Authorization'] = 'Basic ' . base64_encode($uri['user'] . (isset($uri['pass']) ? ':' . $uri['pass'] : ''));
+    $options['headers']['Authorization'] = 'Basic ' . base64_encode($uri['user'] . (isset($uri['pass']) ? ':' . $uri['pass'] : ':'));
   }
 
   // If the database prefix is being used by SimpleTest to run the tests in a copied