quota rules for mail users

[mkawada at redhat.com]

Dear All,

Is it possible to make quota rules under $HOME/Maildir/* mailboxes with 
a specific command such as 'edquota' when the first email arrives at the 
$HOME/Maildir/{new,cur,tmp} of a user. In the below example, the <UserB> 
is the one who gets an email for the first time.

edquota  -p  <UserA> <UserB>

---man edquot---
-p, --prototype=protoname
Duplicate the quotas of the prototypical user specified for each user 
specified. This is the normal mechanism used to initialize quotas for 
groups of users.
---

To configure quotas in postfix/dovecot environment, it seems that you 
need to use dovecot-lda plugin, and then my exact question is as follows:

Is it possible to automatically run any commands or scripts in order to 
set a quota rule to $HOME/Maildir/* mailboxes when users receive an 
email for the first time? I just found the post-login service allows you 
to execute scripts after authentication in the following URL, but I have 
not found the exact way to make it.

http://www.dovecot.org/list/dovecot/2009-November/044279.html

Any comments/suggestions would be greatly appreciated.

-- 
Masaharu Kawada