Pango updates for Leopard.

* Use keg-only fontconfig and Cairo formulas.

Formula/pango.rb

@@ -8,6 +8,11 @@ class Pango <Formula
   depends_on 'pkg-config'
   depends_on 'glib'
 
+  if MACOS_VERSION < 10.6
+    depends_on 'fontconfig' # Leopard's fontconfig is too old.
+    depends_on 'cairo' # Leopard doesn't come with Cairo.
+  end
+
   def install
     system "./configure", "--prefix=#{prefix}", "--with-x"
     system "make install"