I could be wrong but my experience shows me that CHKUSER_MBXQUOTA is a percentage of the users total quota. I use CHKUSER_MBXQUOTA="98" here and it works as I expect it too, ie rejecting mail when the users quota is 98% used.
Thanks Rick, it was a case of me not reading the docs properly. I've set the environment variable and it does as I was expecting. :)
This email has been sent to you by Scott Clark mail at scottclark dot me dot uk. Visit me @ http://www.scottclark.me.uk/
The views and opinions expressed in this email are the author's own.
This email is intended for the exclusive use of the addressee only. If you are not the intended recipient, you should not use the contents nor disclose them to any other person and you should immediately notify the sender and delete the email.