foolproof method of determining Kerberos version?

[Ezra Peisach]

Well, I do not have a foolproof manner, but at configuration time,
you might try "krb5-config --version".

Personally, I am wary of anything outside depending on a krb5 internal
structure. If you need access to some internal information,
maybe a krb5 extension to gss is needed to give you access... I would
send it to krb5-bugs. Also - if the serialization code is broken -
send that in too...

Ezra