Requiring TLS in all clients will force non-compliant clients.
Also, after looking at TLS more closely, TLS poses additional
interoperability concerns (specifically, there are no required
ciphers, only recommended ones.) If a TLS-capable server and
client can't find a common cipher to use, then they either have to
send data in the clear or drop the connection, which either kills
security or interoperability (take your pick)...
As much as I hate to say it, we're getting back to requiring Digest
alone (with the appropriate caveats in the implementer's guide).
-- ______________________________________________________________________ Michael Sweet, Easy Software Products mike@easysw.com Printing Software for UNIX http://www.easysw.com