[mew-int 3139] maildir configuration

Hello,

I'm having some trouble getting mew to work with a maildir.  I use getmail4 to download messages to a maildir at ~/gmail-archive

I have the following configuration in my mew.el

(setq mew-config-alist
      '(
      ;; various other mailboxes
        ("archive"
         ("proto" . "+")
         ("mailbox-type" . "mbox")
         ("mbox-command" . "incm")
         ("mbox-command-arg" . "-a -d /path/to/gmail-archive")
         )))

However, visiting +inbox; pressing s, and choosing "update" doesn't cause incm to fetch the messages from my maildir to +inbox.  When I run "incm" manually from a terminal like this:

~/Mail/inbox$ incm -u -d ~/gmail-archive/

the messages do end up in my inbox.  Does anybody have an idea where the problem might be?

Thomas