I've always had S/mime in the back of my mind as an alternative for intranet/internal secure messaging (with optional escrow/archiving) - the assumption being t

I've always had S/mime in the back of my mind as an alternative for intranet/internal secure messaging (with optional escrow/archiving) - the assumption being that users would all have certs, there'd be a directory (ldap) - and things would be ok-is(granted metadata would be an issue). Never had i dreamt that S/mime didn't use a sane authenticated cipher configuration (if only by public key signature wrapping traditional ciphertext). I mean that was the whole concept of S/mime, right? Federated key/trust and public key cryptography?