The funny part is that all the pieces (FreeType, HarfBuzz, Pango) are really well done, just FreeType isn't tweaked properly. :/
On a karmic box:
$ apt-get source libfreetype6
$ grep -h TT_CONFIG_OPTION_BYTECODE freetype-2.3.9/debian/patches-freetype/*
-/* #define TT_CONFIG_OPTION_BYTECODE_INTERPRETER */
+#define TT_CONFIG_OPTION_BYTECODE_INTERPRETER