diff --git a/pkgs/applications/video/mythtv/default.nix b/pkgs/applications/video/mythtv/default.nix
index 1bfd0f7b755..24023b1cfc3 100644
--- a/pkgs/applications/video/mythtv/default.nix
+++ b/pkgs/applications/video/mythtv/default.nix
@@ -1,5 +1,5 @@
 { stdenv, fetchurl, which, qt3, x11
-, libXinerama, libXv, libXxf86vm, libXrandr, libXmu
+, libX11, libXinerama, libXv, libXxf86vm, libXrandr, libXmu
 , lame, zlib, mesa}:
 
 assert qt3.mysqlSupport;
@@ -13,13 +13,16 @@ stdenv.mkDerivation {
     md5 = "52bec1e0fadf7d24d6dcac3f773ddf74";
   };
 
-  patches = [./settings.patch];
-  configureFlags = "--disable-joystick-menu";
+  configureFlags = "--disable-joystick-menu --x11-path=/no-such-path --dvb-path=/no-such-path";
 
   buildInputs = [
-    which qt3 x11 libXinerama libXv libXxf86vm libXrandr libXmu
+    which qt3 x11
+    libX11 libXinerama libXv libXxf86vm libXrandr libXmu
     lame zlib mesa
   ];
   
-  inherit qt3;
+  patches = [
+    ./settings.patch
+    ./purity.patch # don't search in /usr/include etc.
+  ];
 }
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index ac448e82ef6..6e6c4c1e6a3 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2431,7 +2431,7 @@ rec {
 
   mythtv = (import ../applications/video/mythtv) {
     inherit fetchurl stdenv which qt3 x11 lame zlib mesa;
-    inherit (xlibs) libXinerama libXv libXxf86vm libXrandr libXmu;
+    inherit (xlibs) libX11 libXinerama libXv libXxf86vm libXrandr libXmu;
   };
 
   gqview = (import ../applications/graphics/gqview) {