[Exim] Partial matching for (e-mail) address lookups?

Hello there,

I'm trying to use whitelist patterns like "*@*.my.domain". However I just learnt
that partial matching only works for domain lookups.

Why is this? I have the following in my Exim4 config file:

  accept  senders       = ${if exists{EXIM_VIRT_DOM_DIR/$domain/whitelist} \
                            {${lookup {$sender_address} partial-lsearch*@ \
                                {EXIM_VIRT_DOM_DIR/$domain/whitelist} \
                                {$sender_address} {}}} {}}
          domains       = +local_domains

I thought I could have whitelist entries like the above by using this construct,
but it doesn't work. I have to remove "partial-" in order to make the above
expression do ANYTHING useful, but then I can only use patterns like
"*@subdomain.my.domain" of course.

Any ideas?

Thanks,

Ralf

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