gdk-pixbuf-set-option missing?

[Mario Kemper <mario kemper googlemail com>]

Is this method already covered by the bindings?
http://library.gnome.org/devel/gdk-pixbuf/stable/gdk-pixbuf-Module-Interface.html#gdk-pixbuf-set-option

I want include the "orientation"-flag when saving jpeg files. Is there
any way to do this with current bindings? 

$pixbuf->get_option('orientation') works fine, btw.

Including text chunks when saving png files does work as well, like
this:
$pixbuf->save( $filename, $filetype, "tEXt::Software" => "MySoftware",
compression => $compression );

Anyone knows how to save the orientation flag?

Regards
Mario