Still receiving Quota warning: mailbox 95% full altough now 20% full

Hello

I am using the quota warnings e-mail feature of dovecot to warn users at 80% and 95%. The issue here is that I have one use who his mailbox is now back down to 20% but he still receives the 95% mailbox full warning mail. Any ideas what could be wrong or what to do?

My dovecot config of the mailbox server can be found here: http://article.gmane.org/gmane.mail.imap.dovecot/80823

Regards ML