[Exim] Address Verification and $address_data

Hi,

I'm trying to convert our current Exim3 config over to Exim4 and have
now come a bit of a cropper with the fact that it no longer has the
concept of local users.

I'm trying to implement the email address verification at rcpt time
using the ACLs. All our users are stored in LDAP and what I don't want
to do is have to do a lookup at verification time and then a further
lookup at delivery time. So, what I was wondering is :-

1) Does 'address_data = ...' get handled within a verify only router ?
eg (based on previous postings) :-

ldaplookup:
    driver       = redirect
    domains      = +our_domains
    address_data = ldap;ldap::///LDAPBASE??one?(uid=${quote_ldap:$local_part})
      data         =
    verify_only

# Other LDAP lookups performed here for differing criteria
...

verify_address:
    driver    = accept
    condition = ${if match {$address_data} {homeDirectory} {yes} {no}}
    verify_only

final_delivery:
    driver      = accept
    transport   = maildir_delivery
    no_verify

2) Is $address_data linked to each individual address within an SMTP
session. Ie if multiple 'rcpt to:' entries are given, will that result
in a different $address_data at the point the router 'final_delivery' is
run for each of the addresses provided ? (I hope that's clear - it is in
my head)

If none of this works, is there any way that I can return a different
error than 'Unrouteable address' without modifying the code ?

Thanks,
Jerry.
--
Supanet Ltd., Communications House,
Jeremy.Nicholls@???
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www.supanet.net.uk
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