Sammenligning m. andre MTA'er

                      sendmail   exim  smail  zmailer  qmail  postfix
DFSG license              Y       Y      Y       Y       N       Y
sendmail compat           Y       Y      Y       N       N       Y
easy to configure         N       Y      N       N      [1]      Y
regexp in config files    N       N      N       N       N       Y
secure design             N       N      N       N       Y       Y
secure in practice        N      [2]    [3]     [4]      Y       Y
fast                      N       N      N       Y       Y       Y
copes with heavy load     N       N      N       Y       Y       Y
[1] some say yes, some say no.  i think qmail is clumsy to configure.
    it's certainly not as easy as either postfix or exim.
[2] unknown.  AFAIK, exim hasn't had any major security incidents.
[3] unknown.  probably not.  there have been problems in the past.
[4] i don't know enough about zmailer to comment, i only trialled it
    for a few days.