DKIM on messages

Hi all, Minor issue really but a fair chunk of the emails I get from the internals list end up in spam due to what looks like the DKIM signatures being incorrect. If a message is DKIM signed, the signed part usually contains subject and body, this is then hashed and appended to the headers, after its been sent to the mailing list (where the signature is correct) the mailing list then prepends [PHP-DEV] to the subject and sometimes (not sure when but its not every request) puts an unsubscribe link in the body. As the message content has now changed, the signature also fails to verify. It looks like ezmlm is used, there is an option for headerremove which DKIM-Signature could be added to (https://manpages.debian.org/experimental/ezmlm-idx/ezmlm-send.1.en.html) this would prevent the signature being attached and therefore pass. I imagine this is a fairly small issue, but it seems an easy fix also for someone with access to the mailing list. Would it be possible for this to be applied ? as mentioned earlier this isnt major but I can't imagine I am the only one who has failures because of this. Thanks Scott