dovecot - Oct 2012 - Snarf plugin

I've now upgraded dovecot from 2.0.21 to 2.1.10 and the good news is I no
longer see dovecot crashing when loading the snarf plugin however snarf
still does not do anything except make the inbox disappear.

I've come to the conclusion that either snarf does not actually work,
possible, but I doubt it, or more likely I have a configuration issue
preventing it from working.

The system is simple, all email is stored in /var/spool/mail/{username}
and I want all the mail moved to ~/mbox when the user logs in via imap,
similar to uw-imap.

Any guidance would really be appreciated.

Thanks, Jeff

dovecot -n
# 2.1.10: //etc/dovecot/dovecot.conf
# OS: Linux 3.6.2-1.fc16.x86_64 x86_64 Fedora release 16 (Verne)
mail_debug = yes
mail_location = mbox:~/mail:INBOX=~/mbox
mail_plugins = snarf zlib
mbox_write_locks = fcntl
namespace default {
  inbox = yes
  location   prefix   separator = /
}
namespace snarf {
  hidden = yes
  list = no
  location = mbox:/run/dovecot/empty:INBOX=/var/spool/mail/%u:INDEX=MEMORY
  prefix = /snarf
  separator = /
}
passdb {
  driver = pam
}
plugin {
  mail_log_events = delete undelete expunge copy mailbox_delete
mailbox_rename
  mbox_snarf = ~/mbox
  snarf = /snarf/INBOX
}
service imap-login {
  inet_listener imap {
    address = localhost
  }
}
service pop3-login {
  inet_listener pop3 {
    address = localhost
  }
}
ssl_cert = </etc/pki/tls/certs/XYZZY.pem
ssl_key = </etc/pki/tls/certs/XYZZY.pem
userdb {
  driver = passwd
}
protocol imap {
  mail_plugins = snarf zlib imap_zlib
}


syslog:

Oct 24 13:33:27 xyzzy dovecot: master: Warning: SIGHUP received -
reloading configuration
Oct 24 13:33:27 xyzzy dovecot: imap: Server shutting down. in=277 out=106519
Oct 24 13:33:27 xyzzy dovecot: imap: Server shutting down. in=422 out=2893
Oct 24 13:33:29 xyzzy dovecot: imap-login: Login: user=<jeff>,
method=PLAIN, rip=::1, lip=::1, mpid=28089, secured,
session=<L6okfNHM2AAAAAAAAAAAAAAAAAAAAAAB>
Oct 24 13:33:29 xyzzy dovecot: imap: Debug: Loading modules from
directory: /usr/lib64/dovecot
Oct 24 13:33:29 xyzzy dovecot: imap: Debug: Module loaded:
/usr/lib64/dovecot/lib05_snarf_plugin.so
Oct 24 13:33:29 xyzzy dovecot: imap: Debug: Module loaded:
/usr/lib64/dovecot/lib20_zlib_plugin.so
Oct 24 13:33:29 xyzzy dovecot: imap: Debug: Module loaded:
/usr/lib64/dovecot/lib30_imap_zlib_plugin.so
Oct 24 13:33:29 xyzzy dovecot: imap(jeff): Debug: Effective uid=500,
gid=500, home=/home/jeff
Oct 24 13:33:29 xyzzy dovecot: imap(jeff): Debug: Namespace default:
type=private, prefix=, sep=/, inbox=yes, hidden=no, list=yes,
subscriptions=yes location=mbox:~/mail:INBOX=~/mbox
Oct 24 13:33:29 xyzzy dovecot: imap(jeff): Debug: fs:
root=/home/jeff/mail, index=, control=, inbox=/home/jeff/mbox, altOct 24
13:33:29 xyzzy dovecot: imap(jeff): Debug: Namespace snarf:
type=private, prefix=/snarf, sep=/, inbox=no, hidden=yes, list=no,
subscriptions=yes
location=mbox:/run/dovecot/empty:INBOX=/var/spool/mail/jeff:INDEX=MEMORY
Oct 24 13:33:29 xyzzy dovecot: imap(jeff): Debug: fs:
root=/run/dovecot/empty, index=, control=, inbox=/var/spool/mail/jeff,
altOct 24 13:33:29 xyzzy dovecot: imap(jeff): Disconnected: Logged out in=117
out=1504

Just thought I'd follow up on my original post, I got the snarf plugin 
to work properly with some help from Jonathan at PSU (need to give 
credit where credit is due)

For anybody else looking for the configuration here is the relevant 
output from dovecot -n

# 2.1.10: //etc/dovecot/dovecot.conf
# OS: Linux 3.6.2-1.fc16.x86_64 x86_64 Fedora release 16 (Verne) ext4
mail_location = mbox:/home/%u/mail:INBOX=/home/%u/mbox
mail_plugins = snarf zlib
namespace Snarf {
   hidden = yes
   list = no
   location = mbox:/home/%u/mbox:INBOX=/var/spool/mail/%u:INDEX=MEMORY
   prefix = ~~Snarfbox/
   separator = /
}
namespace default {
   inbox = yes
   location    prefix    separator = /
}

plugin {
     snarf = ~~Snarfbox/INBOX
}

What I found was I was specifying the snarf mbox location as ~/mbox, 
once I changed to /home/%u/mbox things started working.

Thanks,
Jeff