owa 2010: external web app url for EV server

Does anyone know if this setting in advanced desktop policy for owa still works in EV 9.0?  It seems to be completely dropped from the EV 9.0 Admin guide (I also checked in EV 8.0 and it's not there either).

Basically, this is for OWA users from outside to be able to access AE or search: since starting with Exch. 2007 we can no longer proxy via the exchange CAS and need direct access to the EV box, it would make sense to publish a different external url for EV than the internal url.  I know this can be done also via changes in web.config on CAS servers, however it would be simpler if this setting still works.

Thanks,

Fremont