anchor.diff:      gtkspell aspell
       gstreamer gst_plugins_base startupnotification
       libxml2 nss nspr farsight2
  -    libXScrnSaver ncurses python
  +    xorg.libXScrnSaver ncurses python
       avahi dbus dbus_glib intltool libidn
  -    libICE libXext libSM
  +    xorg.libICE xorg.libXext xorg.libSM
     ]
     ++ (lib.optional (openssl != null) openssl)
     ++ (lib.optional (gnutls != null) gnutls)
     ++ (lib.optional (libgcrypt != null) libgcrypt);
   
     propagatedBuildInputs = [
  -    pkgconfig gtk perl perlXMLParser gettext
  +    gtk perl perlXMLParser gettext
     ];
   
     patches = [./pidgin-makefile.patch ./add-search-path.patch ];
  
positive.code: { stdenv, fetchurl, pkgconfig, gtk, gtkspell, aspell
  , gstreamer, gst_plugins_base, startupnotification, gettext
  , perl, perlXMLParser, libxml2, nss, nspr, farsight2
  , libXScrnSaver, ncurses, avahi, dbus, dbus_glib, intltool, libidn
  , lib, python, libICE, libXext, libSM
  , openssl ? null
  , gnutls ? null
  , libgcrypt ? null
  
negative.code: stdenv.mkDerivation rec {
    name = "pidgin-${version}";
    majorVersion = "2";
    version = "${majorVersion}.10.12";
  
    src = fetchurl {
      url = "mirror://sourceforge/pidgin/${name}.tar.bz2";
      sha256 = "1pgzfwgf7vl72hppdr2v8gd8dlbvkymkidxj0ff792gyzvq26x9c";
    };
  
    inherit nss ncurses;
  