freeswitch: updating to stable 1.2.3

I'll avoid using the git version; I'm less sure if it's better than the
released stable.

pkgs/servers/sip/freeswitch/default.nix

@@ -1,21 +1,16 @@
-{ fetchgit, stdenv, ncurses, curl, pkgconfig, gnutls, readline, openssl, perl, libjpeg
-, libzrtpcpp, autoconf, automake, libtool }:
+{ fetchurl, stdenv, ncurses, curl, pkgconfig, gnutls, readline, openssl, perl, libjpeg
+, libzrtpcpp }:
 
 stdenv.mkDerivation rec {
-  name = "freeswitch-git-0db52e6";
+  name = "freeswitch-1.2.3";
 
-  src = fetchgit {
-    url = "git://git.freeswitch.org/freeswitch.git";
-    rev = "0db52e6e556fce584f1850c3a3b87c8f46ff87c5";
-    sha256 = "5cc7161c1ba64c5faf3dda2669e9aafd529eaa66be2fd83f284304444bcab9ff";
+  src = fetchurl {
+    url = http://files.freeswitch.org/freeswitch-1.2.3.tar.bz2;
+    sha256 = "0kfvn5f75c6r6yp18almjz9p6llvpm66gpbxcjswrg3ddgbkzg0k";
   };
 
-  preConfigure = ''
-    ./bootstrap.sh
-  '';
-
   buildInputs = [ ncurses curl pkgconfig gnutls readline openssl perl libjpeg
-    autoconf automake libtool libzrtpcpp ];
+    libzrtpcpp ];
 
   meta = {
     description = "Cross-Platform Scalable FREE Multi-Protocol Soft Switch";