Sendmail should be linked against libsaslauth2.so /etc/mail/sendmail.mc: define(`confAUTH_OPTIONS', `A y')dnl TRUST_AUTH_MECH(`LOGIN PLAIN CRAM-MD5')dnl define(`confAUTH_MECHANISMS', `EXTERNAL GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl /etc/sysconfig/saslauthd: MECH=shadow /usr/lib/sasl2/Sendmail.conf: pwcheck_method: saslauthd mech_list: LOGIN PLAIN