diff --git a/pkgs/applications/networking/irc/chatzilla/default.nix b/pkgs/applications/networking/irc/chatzilla/default.nix
index 01cb74a0392d..765066bb4371 100644
--- a/pkgs/applications/networking/irc/chatzilla/default.nix
+++ b/pkgs/applications/networking/irc/chatzilla/default.nix
@@ -1,12 +1,12 @@
 { stdenv, fetchurl, unzip, firefox, makeWrapper }:
 
 stdenv.mkDerivation rec {
-  name = "chatzilla-0.9.90.1";
+  name = "chatzilla-0.9.91";
 
   src = fetchurl {
     # Obtained from http://chatzilla.rdmsoft.com/xulrunner/.
     url = "http://chatzilla.rdmsoft.com/xulrunner/download/${name}.en-US.xulapp";
-    sha256 = "0z38jig91h10cb14rvs30rpg2pgn3v890nyxyy8lxzbv5ncxmngw";
+    sha256 = "1bmjw2wvp8gh7fdl8czkxc55iari6dy672446hps20xixrh8hl8r";
   };
 
   buildInputs = [ unzip makeWrapper ];