Are you getting the below error messages on Solaris /var/adm/messages? This error messages is nothing. You can disable the sendmail service in Solaris.
# var/adm/messages Jan 30 04:04:26 itsiti sendmail[1234]: [ID 1112223 mail.crit] My unqualified host name (itsiti) unknown; sleeping for retry Jan 30 04:05:09 itsiti sendmail[1234]: [ID 1112223 mail.alert] unable to qualify my own domain name (itsiti) -- using short name Jan 30 05:22:12 itsiti sendmail[1234]: [ID 1112223 mail.crit] My unqualified host name (itsiti) unknown; sleeping for retry
1. Check the sendmail process & service.
# ps -ef | grep sendmail root 1234 2 0 05:11:22 ? 0:00 /usr/lib/sendmail root 1234 4567 0 05:22:03 pts/3 0:00 grep sendmail
# svcs -l svc:/network/smtp:sendmail fmri svc:/network/smtp:sendmail name sendmail SMTP mail transfer agent enabledtruestate online next_state none state_time Sun Jan 30 04:33:43 2011 logfile /var/svc/log/network-smtp:sendmail.log
2. Disable the sendmail service.
# svcadm disable svc:/network/smtp:sendmail
3. Verify by checking the sendmail process
# ps -ef | grep sendmail
