Deleting mailbox problem

[Wouter van Marle]

Hi all,

I've a problem deleting a mailbox in my system. User "wouter" is a admin for cyrus ("admins: wouter" in imapd.conf), this is the user I normally use to access cyradm on localhost.
My mailboxes:
INBOX (with a whole lot of children), my main inbox
wouter.INBOX, the mailbox that I want to delete.

When checking the permissions I get:
mymusic.hk> lam wouter.INBOX
anyone lrs

So I have to give myself delete rights, as user "wouter" is admin, I should have that right automatically. However trying to gain that right, I get the following error:
mymusic.hk> sam wouter.INBOX wouter d
setaclmailbox: wouter: d: System I/O error

Obviously there is something wrong, though I've no idea what to look for now!
The whole INBOX.* hierarchy by the way is stored in /var/spool/imap/w/user/wouter/. The general name "INBOX" is not mentioned there. This all is fine as I'm the only user on this system anyway, at least for the time being.

Wouter.