Problem w/ the Exim pipe transfer

[Morgon Kanter <morgon@surgo.net>]

Hello,

I recently set up a debbugs bug tracking system, and have just tried to send 
it a test bug (after hammering out some other bugs that I introduced ;). 
However, this seems to be some kind of permission problem, but I can't figure 
out where the permissions are wrong, and it's Exim that is complaining. Here 
is the email it returns to me:
---------------------------------------------------------------------------------
This message was created automatically by mail delivery software (Exim).

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  submit@bugs.surgo.net
    Child process of debbugs_pipe transport returned 75 (could mean temporary 
error) from command:
    /usr/lib/debbugs/receive

The following text was generated during the delivery attempt:

------ submit@bugs.surgo.net ------

bugs receive failure: open temporary file: Permission denied
------------------------------------------------------------------------------

I am using Exim 3.36 and Debbugs 2.3-4. I am wondering - where are the 
permissions screwed up, and if that's not it, what is wrong? Here is a copy 
of my pipe transport in my exim.conf:
------------------------------------------------------------------------------
# For debbugs
debbugs_pipe:
  driver = pipe
  command = /usr/lib/debbugs/receive
  user = debbugs
  group = debbugs
  return_output
------------------------------------------------------------------------------

And here is a copy of the directive used (because this isn't a dedicated 
server, there seems to be more than one way to do this):
------------------------------------------------------------------------------
# For debbugs
debbugs:
  driver = smartuser
  transport = debbugs_pipe
  local_parts = 
submit:bugs:maintonly:quiet:forwarded:done:close:request:submitter:control:^\\d+
  domains = bugs.surgo.net
------------------------------------------------------------------------------

Can anyone spot the problem? I really have no idea what's going on in this 
error.

Morgon
-- 
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