[Exim] simple virtual defaults query

Hi

New user of exim, hosting about 20 virtual domains (on sendmail at the
moment), trying to set up a default alias on each domain as a fallback for
unknown addressees...

Mail to unknown addressee is being placed in a new mailbox for that
addressee instead of into the fallback.

Snippets of config files:

/usr/exim/virtual/wirelessnotes.co.uk/aliases...

    *:    dirk@???
    dirk:    dirk@???

transport... (from mailing list archive)...

virtual_localdelivery:
    driver = appendfile
    create_directory = true
    directory_mode = 700
    file = /var/spool/virtual/${domain}/${local_part}
    user = exim
    group = exim
    mode = 660

director... (sort of from O'Reilly Exim book)

virtual:
    driver = aliasfile
    domains = lsearch;/usr/exim/domains
    file = /usr/exim/virtual/${domain}/aliases
    search_type = lsearch*
    transport = virtual_localdelivery
    no_more

Running "exim -bt -d9 mary@???" shows a failed lookup for
'mary', followed by a successfull lookup for '*' but indicates that the
local_part is still 'mary'.

Any pointers gratefully received :-)

Dirk