Index: common.inc
===================================================================
--- common.inc
+++ common.inc
@@ -227,6 +227,17 @@
 
   $url = url($path, $query, $fragment, TRUE);
 
+  if (ini_get('session.use_trans_sid') && session_id() && !strstr($url, session_id())) {
+    $sid = session_name() . '=' . session_id();
+
+    if (strstr($url, '?') && !strstr($url, $sid)) {
+      $url = $url .'&'. $sid;
+    }
+    else {
+      $url = $url .'?'. $sid;
+    }
+  }
+
   // Before the redirect, allow modules to react to the end of the page request.
   module_invoke_all('exit', $url);