explicitly set rpath for zlib otherwise librsvg might be linked to system zlib.

component/librsvg/buildout.cfg

@@ -37,4 +37,4 @@ configure-options =
 environment = 
   PATH=${gdk-pixbuf:location}/bin:${glib:location}/bin:${libxml2:location}/bin:${pkgconfig:location}/bin:${pango:location}/bin:%(PATH)s
   PKG_CONFIG_PATH=${cairo:location}/lib/pkgconfig:${fontconfig:location}/lib/pkgconfig:${freetype:location}/lib/pkgconfig:${gdk-pixbuf:location}/lib/pkgconfig:${glib:location}/lib/pkgconfig:${kbproto:location}/lib/pkgconfig:${libX11:location}/lib/pkgconfig:${libpng:location}/lib/pkgconfig:${libXau:location}/lib/pkgconfig:${libXrender:location}/lib/pkgconfig:${libcroco:location}/lib/pkgconfig:${libxcb:location}/lib/pkgconfig:${libxml2:location}/lib/pkgconfig:${pango:location}/lib/pkgconfig:${pixman:location}/lib/pkgconfig:${zlib:location}/lib/pkgconfig:${xorg-libpthread-stubs:location}/lib/pkgconfig:${xproto:location}/lib/pkgconfig
-  LDFLAGS=-L${bzip2:location}/lib -Wl,-rpath=${bzip2:location}/lib
+  LDFLAGS=-L${bzip2:location}/lib -Wl,-rpath=${bzip2:location}/lib -Wl,-rpath=${zlib:location}/lib