[exim] simple smtp auth via /etc/passwd..

I found this in the archives.. and it seems to work for what I'm looking
for atm..

http://www.exim.org/pipermail/exim-users/Week-of-Mon-20011105/031982.html

Yet when I try and use swaks to test.. I get this in the logs..

2006-07-24 22:50:49 plain authenticator failed for
cpe-124-161-112-193.nyc.res.rr.com (milenko.at.home) [124.161.112.193]:
435 Unable to authenticate at present (set_id=bcook): failed to open
/etc/master.passwd for linear search: Permission denied (euid=26 egid=6)
inside "and{...}" condition

I could use a file for auth.. but is this still possible?

Using the stock configure.. I am not sure this can be overcome.. as
no_deliver_drop_privilege is already (default)

fwiw here are my authenticators:

begin authenticators

plain:
  driver = plaintext
  public_name = PLAIN
  server_condition = "${if and {{!eq{$2}{}}{!eq{$3}{}} \
                          {crypteq{$3}{${extract{1}{:} \
{${lookup{$2}lsearch{/etc/master.passwd}{$value}{*:*}}}}}}}{1}{0}}"
  server_set_id = $2

login:
  driver = plaintext
  public_name = LOGIN
  server_prompts = "Username:: : Password::"
  server_condition = "${if and {{!eq{$1}{}}{!eq{$2}{}} \
                          {crypteq{$2}{${extract{1}{:} \
{${lookup{$1}lsearch{/etc/master.passwd}{$value}{*:*}}}}}}}{1}{0}}"
  server_set_id = $1

Thanks in advance