passwd file for quota

[Cliff Hayes]

I need to implement quota.
I read as much as I could including
http://wiki2.dovecot.org/HowTo/SimpleVirtualInstall
But my current /etc/passwd file does not have the password in it as 
shown in dovecot docs ... there is an x where the password should be.
I created a program that creates a passwd file in the proper format with 
the proper extra quota fields for all users (except it has an x where 
the password should be).  I plan to store it in /etc/dovecot
How do I get dovecot to stop looking at /etc/passwd and start looking at 
/etc/dovecot/passwd?
And hopefully that will not affect how it gets the password (pam) 
because when users change their password from webmail of course dovecot 
will need to be looking in the same place.

# dovecot -n output
# 2.0.9: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-431.29.2.el6.x86_64 x86_64 Scientific Linux release 
6.5 (Carbon)
auth_failure_delay = 5 secs
auth_username_format = %Ln
auth_verbose_passwords = plain
first_valid_uid = 9
mail_access_groups = mail
mail_location = maildir:~/Maildir
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope 
encoded-character vacation subaddress comparator-i;ascii-numeric 
relational regex imap4flags copy include variables body enotify 
environment mailbox date
mbox_write_locks = fcntl
passdb {
   driver = pam
}
plugin {
   sieve = ~/.dovecot.sieve
   sieve_after = /dovecotSieveAfter/
   sieve_dir = ~/sieve
}
protocols = imap lmtp sieve
service managesieve-login {
   inet_listener sieve {
     port = 4190
   }
}
ssl_ca = </etc/pki/dovecot/certs/intermediate20150202.crt
ssl_cert = </etc/pki/dovecot/certs/avalon20150202.crt
ssl_key = </etc/pki/dovecot/private/avalon20150129.key
ssl_verify_client_cert = yes
userdb {
   driver = passwd
}
protocol lmtp {
   log_path = /var/log/dovecot-lmtp.log
   mail_plugins = " sieve"
}
protocol lda {
   log_path = /var/log/dovecot-lda.log
   mail_plugins = " sieve"
}