As far as I can tell, X.500/LDAP servers and X.500<->LDAP gateways may use another mapping between T.61 and Unicode than the one in [Strprep] Appendix A for transfer and storage of values, *except* for string matching, for which [Strprep] section 2.1 says:
TeletexString [X.680][T.61] values are transcoded to Unicode as described in Appendix A.
This thread gives me the heeby-jeebies! We cannot possibly spend this much time on T.61. I suggest that we say that usage of T.61 is a SHOULD NOT and be done with it. The only situations where T.61 might appear that I can think of are LDAPv2 (historic and therefore out of scope) and Certificates with DirectoryString, but new certificates MUST use only UTF8String (if I remember right) since about a year ago so where exactly is the applicability of this?
MVH leifj