diff --git a/mozilla/toolkit/components/url-classifier/src/nsUrlClassifierStreamUpdater.cpp b/mozilla/toolkit/components/url-classifier/src/nsUrlClassifierStreamUpdater.cpp
index de91215fbba..d7118db61ef 100644
--- a/mozilla/toolkit/components/url-classifier/src/nsUrlClassifierStreamUpdater.cpp
+++ b/mozilla/toolkit/components/url-classifier/src/nsUrlClassifierStreamUpdater.cpp
@@ -101,7 +101,8 @@ TableUpdateListener::OnStartRequest(nsIRequest *request, nsISupports* context)
   nsresult status;
   rv = httpChannel->GetStatus(&status);
   NS_ENSURE_SUCCESS(rv, rv);
-  if (NS_ERROR_CONNECTION_REFUSED == status) {
+  if (NS_ERROR_CONNECTION_REFUSED == status ||
+      NS_ERROR_NET_TIMEOUT == status) {
     // Assume that we're overloading the server and trigger backoff.
     mErrorCallback->HandleEvent(nsCString());
     return NS_ERROR_ABORT;