help

my system is solaris7,i once used qmail as my MTA and 
"ln -s /export/home/user/Mailbox /var/mail/user",it work fine

but now, i want to switch from qmail to sendmail8.9.3,and use procmail as LDA
my question is:
1,how should i configure my "mc" file to use procmail as LDA?
2,how should i configure procmail's "authenticat.c " file to
  let procmail deliver mail to /export/home/user/Mailbox?
please give me more details,because i was totally lost