Connecting to a newly installed IMAP server using mutt

I have installed the bincimapd IMAP server on one of my machines. I can
access the IMAP mail server via telnet as follows:

Trying 10.0.0.8...
Connected to markhobley.yi.org.
Escape character is '^]'.
* OK Welcome to Binc IMAP Copyright (C) 2002-2005 Andreas Aardal Hanssen
at 2008-06-16 09:09:54 +0100
1 login mark password
1 OK LOGIN completed
2 CAPABILITY
* CAPABILITY IMAP4rev1
2 OK CAPABILITY completed
3 logout
* BYE Binc IMAP shutting down
3 OK LOGOUT completed
Connection closed by foreign host.

At the moment, my mail directory is empty (apart from the .password
file), and I have not yet composed or received any mail.

I try to connect my mail client to the imap server as follows:

mutt -f imap://neptune

Username at neptune: mark
Password for mark@neptune:

I get an error as follows, and the mail client immediately exits, before
I can do anything on the client.

SELECT failed: failed to open "./new/" (Permission denied)

Presumably, the client is trying to read from a directory new, which
does not yet exist.

Is there some configuration change that I should be making on the client
side, to create the empty maildir tree?

I guess I am expecting to see folders for INBOX and SENT ITEMS
(a bit like those in "Outlook Express").

Thanks in advance to anyone who can help.

--
Mark Hobley,
393 Quinton Road West,
Quinton, BIRMINGHAM.
B32 1QE.