>In KDC, krb5_db_allowed_to_delegate_from() returns KRB5_PLUGIN_OP_NOTSUPP because 'v->allowed_to_delegate_from == NULL'. > >Is S4U2Proxy not supported by default KDB module (db2)? Sadly, no. It's on my list to submit a patch for that, but it's low priority for me as we have no direct need for S4U2Proxy at this time but I could see a future use for it. --Ken