[Exim] From exim3 to exim4 migration

Hello All.

I'm migrating from exim3 to exim4.
Because many things was been changed, I'm confuse.
For example, with exim3 I have folowing in directors:

virtual_localuser:
    driver = aliasfile
    transport = virtual_localdelivery
    domains = lsearch;/var/virtual/domains
    file = /var/virtual/auth/$domain/passwd
    search_type = lsearch
    no_more

But I'm not understand how I can same in exim4.
"aliasfile" was been removed in exim4. With
"redirect" router I could not configure search
condition.

Help me, please.

--
With best wishes,
Victor Vislobokov
Perm, Russia