[exim] My errors_to gets wiped out

In my ACL I set an acl_m_delivery variable.

set acl_m_delivery = ${lookup{$local_part}nwildlsearch{/etc/deliverydat}}

Then I have a router that uses the info to set errors_to

errors_to = ${quote_local_part:${local_part:$address_data}}@
${domain:$address_data}

The email passes through a 2nd router (manualroute) where things get weird.

If I set route_data using the ACL variable, my errors_to is left in tact.

route_data = ${extract{smarthosts}{$acl_m_delivery}}

If I do the expansion again from scratch rather than using the ACL_M
variable it will blow away the errors_to value that was set in my 1st
router...

route_data = ${extract{smarthosts}{
${lookup{$local_part}nwildlsearch{/etc/deliverydat}} }}

What causes a lookup a 2nd time, rather than using the variable to wipe out
errors_to ???


Robert G.