PKCS12 structure.
Either B<pkey>, B<cert> or both can be B<NULL> to indicate that no key or
-certficate is required. In previous versions both hasves to be present or
+certficate is required. In previous versions both had to be present or
a fatal error is returned.
B<nid_key> or B<nid_cert> can be set to -1 indicating that no encryption