diff --git a/pkgs/applications/networking/mailreaders/thunderbird/default.nix b/pkgs/applications/networking/mailreaders/thunderbird/default.nix
index 2cbac78ddca..ef56ef07f75 100644
--- a/pkgs/applications/networking/mailreaders/thunderbird/default.nix
+++ b/pkgs/applications/networking/mailreaders/thunderbird/default.nix
@@ -13,7 +13,7 @@
 
 
 stdenv.mkDerivation {
-  name = "thunderbird-1.5";
+  name = "thunderbird-1.5.0.4";
 
   builder = ./builder.sh;
   src = fetchurl {