[Exim] lookup syntax problems

Hi Guys,

i've dome a script to import some infos from an external repository to 2 cdb files called

shortname.cdb (containing local_part)
mail.cdb (containing local_part@local_domain)

I would like to test incoming recipients during smtp dialogue but i have some problems with syntax.
This conditions fails with an error:

  accept  domains       = +local_domains
          endpass
          message       = unknown user
          condition     = "${if or {\
                        {!eq {${lookup{$local_part}cdb{/etc/exim/shortname.cdb} {$local_part}}}{}}\
                        {!eq {${lookup{$local_part@$domain}cdb{/etc/exim/mail.cdb} {$local_part@$domain}}}{}}\
                }{no}{yes}}"
          verify        = recipient

What's wrong? Can you help me plz?

Thanks

Riccardo