[exim] DKIM

Hi All,

I have DKIM set up and working for out going mail and verification for
in coming.
For in coming mail I check the result with
${lookup dkim{$sender_address_domain}}.
This works in most circumstances but gmail and yahoo seam to check
against the value of d=some.domain.com in the dkim sig.
Reading the spec this is the correct way to validate DKIM sigs.
Is there any way to do the same with exims dkim validation?

Many thanks

David