Maildir quota notify for user or admin

Is there any way how to setup quota monitoring for users Maildirs - or even users homedirs ?

Can virtualmin or webmin notify admin/user about this situation.
I was trying to setup this in server and status monitoring but without any success.

Thanks for any advice.

I have written little script in zsh which checks users quota and notifies
admin about it. You can find it attached below.

Thanks to all.

As always - it must be with txt suffix.

Again adding file. [file name=checking_quota.txt size=693]http://www.virtualmin.com/components/com_fireboard/uploaded/files/checking_quota.txt[/file]