[exim] Transport storing informations

Hi,

is it possible to have an sql select inside a transport who queries
informations and stores them in reusabel variables ..

i.e.
     ..
     var_x = $lockup{select id from mailboxes where localpart='$localpart'}
     transport_filter = 'filterfile' '$localpart@$domain' '$var_x'
     ...

?

Marius