Mutt detects new mail in old mailbox

[Wouter Hanegraaff]

When I browse through my mailboxes with c<Space>.., one of the boxes
that is supposed to have new mail doen't have new mail at all.
This happens very often. When I am in that folder, mutt even sometimes
explicitely tells me there's new mail in that box.
For all I know, this happens only with one very small mailbox.

Anyone encountered this too?

I'm using Mutt 0.95.3i (1999-02-12)

Wouter...