[Exim] Exim 4.10 on OS X Server - Relay Problems

Thanks to you folks on this list, I got Exim working for sending and
receiving. However, when I try to relay from home using SMTP_AUTH, I get
the error message
"unrecognized command (500)".

Here is my part of my conf file:

######################################################################
#                       ACL CONFIGURATION                            #
#         Specifies access control lists for incoming SMTP mail      #
######################################################################

begin acl

# This access control list is used for every RCPT command in an incoming
# SMTP message. The tests are run in order until the address is either
# accepted or denied.

acl_check_rcpt:

# Accept if the source is local SMTP (i.e. not over TCP/IP). We do this by
# testing for an empty sending host field.

accept hosts = :

# Deny if the local part contains @ or % or / or | or !. These are rarely
# found in genuine local parts, but are often tried by people looking to
# circumvent relaying restrictions.

  deny    local_parts   = ^.*[@%!/|]

# Accept mail to postmaster in any local domain, regardless of the source,
# and without verifying the sender.

  accept  local_parts   = postmaster
          domains       = +local_domains

# Deny unless the sender address can be verified.

  require verify        = sender

  #############################################################################
  # There are no checks on DNS "black" lists because the domains that contain
  # these lists are changing all the time. However, here are two examples of
  # how you could get Exim to perform a DNS black list lookup at this point.
  # The first one denies, while the second just warns.
  #
  # deny    message       = rejected because $sender_host_address is in a
black list at $dnslist_domain\n$dnslist_text
  #         dnslists      = black.list.example
  #
  # warn    message       = X-Warning: $sender_host_address is in a black
list at $dnslist_domain
  #         log_message   = found in $dnslist_domain
  #         dnslists      = black.list.example
  #############################################################################

# Accept if the address is in a local domain, but only if the recipient can
# be verified. Otherwise deny. The "endpass" line is the border between
# passing on to the next ACL statement (if tests above it fail) or denying
# access (if tests below it fail).

  accept  domains       = +local_domains
          endpass
          message       = unknown user
          verify        = recipient

# Accept if the address is in a domain for which we are relaying, but
again,
# only if the recipient can be verified.

  accept  domains       = +relay_to_domains
          endpass
          message       = unrouteable address
          verify        = recipient

# If control reaches this point, the domain is neither in +local_domains
# nor in +relay_to_domains.

# Accept if the message comes from one of the hosts for which we are an
# outgoing relay. Recipient verification is omitted here, because in many
# cases the clients are dumb MUAs that don't cope well with SMTP error
# responses. If you are actually relaying out from MTAs, you should
probably
# add recipient verification here.

  accept  hosts         = +relay_from_hosts

# Accept if the message arrived over an authenticated connection, from
# any host. Again, these messages are usually from MUAs, so recipient
# verification is omitted.

accept authenticated = *

# Reaching the end of the ACL causes a "deny", but we might as well give
# an explicit message.

  deny    message       = relay not permitted

######################################################################
#                   AUTHENTICATION CONFIGURATION                     #
######################################################################

# There are no authenticator specifications in this default configuration
file.

begin authenticators
fixed_plain:
driver = plaintext
public_name = PLAIN
server_condition = ${if crypteq{$3}
{${extract{1}{:}{${lookup{$2}lsearch{/etc/relayers}{$value}}}}}{yes}{no}
server_set_id = $2

fixed_cram:
driver = cram_md5
public_name= CRAM-MD5
server_secret = ${lookup{$1}lsearch{/etc/relayers}{$value}{fail}}
server_set_id = $1

login:
driver = plaintext
public_name = LOGIN
server_prompts = "Username:: : Password::"
server_condition = ${if
eq{$2}{${lookup{$1}lsearch{/etc/relayers}{$value}{no}}}{yes}{no}}
server_set_id = $1

# End of Exim configuration file

Any help is appreciated.

Thanks in advance,

Dave