[Dovecot] Enabling different quota limits for different users for /etc/passwd as userdatabase on FC3

[ankush grover]

hey friends,

 I am running my company's mail server on FC3 which comprises of
Postfix + Dovecot + MailScanner + Clamav + Squirrelmail + MailWatch +
Spamassassin. I am using Dovecot 0.99.13-3 version on FC3 and I want
to implement Quota limits for the users.

I am using userdatabase as /etc/passwd file (auth_userdb = passwd )
and password database as pam(auth_passdb = pam) for dovecot. I read
the documentation of dovecot but the quota example for /etc/passwd is
missing. I want to have different quota limits for different users
for example Quota limitation will depend upon the users, well there
will be a global quota limit which will takes place if there is no
limit specified for that particular user.

Can anybody guide me how to configure quota's for different users in
dovecot for /etc/passwd as userdatabase and pam as password database.

Please let me know if you need any further inputs.

Thanks & Regards

Ankush Grover