More Exim/Cyrus effort

[Chris Hamilton]

OK, I have used the cyrus call lmtp_downcase_rcpt and it works well.  I 
have since then implemented amavisd-new which
has the feature to send spam to a user+SPAM at domain.com.  I would like to 
use this to automatically have my users receive their spam safely.
When I set the system up I used the autocreateinboxfolders to include 
the SPAM folder.  My users are all virtual.

So now I have switched to trying to send mail to specific folders 
through exim.  I have the following (after amavisd):
#router
localuser:
#  caseful_local_part = false
  driver = accept
  local_part_suffix_optional
  local_part_suffix = +*
  transport = local_delivery

#transport
local_delivery:
  driver = lmtp
  command = /usr/bin/deliver -q -l -a ${lc:$local_part} \
if{ {$local_part_suffix} {-m ${substr_1:${local_part_suffix}}}}  -- 
${lc:$local_part}
  batch_max = 20
  user = cyrus
  delivery_date_add
  return_path_add

All examples I have seen use pipe that have been said to work with 
folders.  Is there a way to get lmtp to work
or do I have to use pipe?  Is there anything I have to do to allow cyrus 
to post to a specific folder with only default permissions?

Also, does anybody have experience sending mail to a shared folder 
without adding the '+' in the name?  I am thinking it will require
a specific router/transport.

Thanks again for any help!

-Chris