Mod_auth_tkt implementation for nginx

Hi all,

I’d like to implement mod_auth_tkt
http://www.openfusion.com.au/labs/mod_auth_tkt/ SSO but I don’t want to
use Apache as front-end.
I’m already using nginx on several hosts and I want SSO for them. I need
SSO on different domains, which is supported by mod_auth_tkt and
mod_auth_tkt is also supported by my backend server (Zope/Plone CMS).

Is there any known implementation of mod_auth_tkt compatible module for
nginx, please?

Thanks,
Radim