diff --git a/pkgs/development/interpreters/python/2.6/default.nix b/pkgs/development/interpreters/python/2.6/default.nix
index 9bf161ffc1aa..ffc4c5d2e1fa 100644
--- a/pkgs/development/interpreters/python/2.6/default.nix
+++ b/pkgs/development/interpreters/python/2.6/default.nix
@@ -63,7 +63,7 @@ let
     C_INCLUDE_PATH = concatStringsSep ":" (map (p: "${p}/include") buildInputs);
     LIBRARY_PATH = concatStringsSep ":" (map (p: "${p}/lib") buildInputs);
 
-    configureFlags = "--enable-shared --with-threads --enable-unicode";
+    configureFlags = "--enable-shared --with-threads --enable-unicode=ucs4";
 
     NIX_CFLAGS_COMPILE = optionalString stdenv.isDarwin "-msse2";
 
diff --git a/pkgs/development/interpreters/python/2.7/default.nix b/pkgs/development/interpreters/python/2.7/default.nix
index 8b24fe004631..b8b25c576c59 100644
--- a/pkgs/development/interpreters/python/2.7/default.nix
+++ b/pkgs/development/interpreters/python/2.7/default.nix
@@ -79,7 +79,7 @@ let
     C_INCLUDE_PATH = concatStringsSep ":" (map (p: "${p}/include") buildInputs);
     LIBRARY_PATH = concatStringsSep ":" (map (p: "${p}/lib") buildInputs);
 
-    configureFlags = "--enable-shared --with-threads --enable-unicode";
+    configureFlags = "--enable-shared --with-threads --enable-unicode=ucs4";
 
     NIX_CFLAGS_COMPILE = optionalString stdenv.isDarwin "-msse2";
     DETERMINISTIC_BUILD = 1;
diff --git a/pkgs/development/interpreters/python/3.2/default.nix b/pkgs/development/interpreters/python/3.2/default.nix
index 2645b5033440..f4103662316e 100644
--- a/pkgs/development/interpreters/python/3.2/default.nix
+++ b/pkgs/development/interpreters/python/3.2/default.nix
@@ -43,7 +43,7 @@ stdenv.mkDerivation {
     done
     ${optionalString stdenv.isDarwin ''export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -msse2"''}
 
-    configureFlagsArray=( --enable-shared --with-threads
+    configureFlagsArray=( --enable-shared --with-threads --with-wide-unicode
                           CPPFLAGS="${concatStringsSep " " (map (p: "-I${p}/include") buildInputs)}"
                           LDFLAGS="${concatStringsSep " " (map (p: "-L${p}/lib") buildInputs)}"
                           LIBS="${optionalString (!stdenv.isDarwin) "-lcrypt"} ${optionalString (ncurses != null) "-lncurses"}"