OWA with Symantec Enterprise Vault

Is this LTM only, or APM? Enterprise Vault seems to only use an internal hostname, and doesn't like it if the wrong hostname is passed to it. Historically I've had to use iRules to modify the hostname in both directions, ie. rewriting clientside OWA hostname to enterprise vault internal hostname in HTTP_REQUEST, and also having to rewrite both Location headers in redirects and links embedded in the page via a REWRITE profile. It's not trivial unfortunately, don't know if it's changed since I had to do this a few years ago.