[Dovecot] per domain quota

[alex]

Hi

I'am using dovecot with quota_rule stored in mysql user table, and quota 
usage stored in mysql dict

###### Quota #############
dict {
   quotadict = mysql:/usr/local/etc/dovecot-quota.conf
}


plugin {
     quota = dict:user::proxy::quotadict
     quota_rule2 = Trash:storage=10%%
     quota_rule3 = Sent:ignore

     #quota_rule = *:storage=10M
}
###################################

Everything works as expected, but I have some inconveniences for domains 
  with large number of mailboxes. Allocating and maintain quota to every 
account it's a hard job.
I just want to implement some flexibility for this situations (ex the 
first  enforcement to be the user quota and the second to be the domain 
quota).
Is there a way to implement such thing in dovecot and what are the 
adjustments that I need to do.

Regards

Alex