[exim] DKIM verification and case-sensitivity of $dkim_cur_s…

Hi all,

I am running exim4.72 on Debian I have the following entry in my acl
section:

acl_check_dkim:

 .ifdef MARCADE_DKIM_SIGNERS
  deny
    message        = marcade.biz could not verify the DKIM signature of this message \
                        Status: $dkim_verify_status [($dkim_cur_signer) - $sender_host_address].
    sender_domains = MARCADE_DKIM_SIGNERS
    dkim_signers   = MARCADE_DKIM_SIGNERS
    dkim_status    = none:invalid:fail
  .endif

Where I have set

MARCADE_DKIM_SIGNERS=paypal.com:ebay.com:aol.com:gmail.com:.... etc

and I have also set:

dkim_verify_signers = $sender_address_domain:$dkim_signers

so that all emails are processed by this ACL.

The problem is that if $dkim_cur_signer is PAYPAL.COM instead of
paypal.com, one of the conditions sender or dkim_status (I'm not sure
which) fails and the email is not rejected if its DKIM signature cannot
be verified.

Is there any way round this

Thanks,

    /Bernard