Here you can see, how to change MTA qmail to any other you can set as simple sendmail or postfix, exim or qmail.
[root@hostshot ~]#ll /etc/alternatives/mta
lrwxrwxrwx 1 root root 23 Aug 31 03:39 /etc/alternatives/mta -> /var/qmail/bin/sendmail
[root@hotshot ~]# alternatives --config mta
There are 4 programs which provide 'mta'.
Selection Command
-----------------------------------------------
*+ 1 /var/qmail/bin/sendmail
2 /usr/sbin/sendmail.exim
3 /usr/sbin/sendmail.postfix
4 /usr/sbin/sendmail.sendmail
Enter to keep the current selection[+], or type selection number: 2
[root@vh115sj ~]# /etc/init.d/qmail stop
Stopping : [root@hotshot ~]# /etc/init.d/exim restart
Shutting down exim: [ OK ]
Starting exim: [ OK ]
[root@hotshot ~]# echo " for shrikant " | mail -s " for shrikant " shrikant.lokhande@betterlabs.net
;) Its done. Please comment if any issue.
