Bob wrote an excellent message explaining PrintableString and T61String.
Although T61String could conceivably accomodate my CN mappings for e-mail
addresses, I think I'll stick with PrintableString and the X.400
encodings. Why? There are already standards for including non-ASCII
character sets in e-mail addresses (MIME part 2), encoded in ASCII, and
those standards can handle more than just the T.61 character set.
This shouldn't preclude using T.61 for other kinds of PEM DN's though.
Cheers,
Rhys.