This is an old revision of the document!
It is always best practice to build .cf file from .mc
m4 sendmail.mc > /etc/sendmail.cf
when you modify /etc/mail/aliases.
Possibly you see following message.
alias database /etc/mail/aliases.db out of date
Simply run following and will fix it.
newaliases
to change outgoing IP on your sendmail server.
change following variable.
O ClientPortOptions=Family=inet, Address=192.168.1.22
NOTE : change 192.168.1.22 with your IP.