[exim] Experimental SPF spec...

>From the Exim-4.66/doc/experimental-spec.txt file, it says the following
about SPF:

*snip*

This assumes that the libspf2 files are installed in
their default locations.

You can now run SPF checks in incoming SMTP by using the "spf"
ACL condition in either the MAIL, RCPT or DATA ACLs. When
using it in the RCPT ACL, you can make the checks dependend on
the RCPT address (or domain)...

*snip*

It seems to be a glaring omission that you can't use libspf2 in the HELO
ACL. It seems like this is an Exim deficiency or am I missing something?
Can the experimental SPF Exim spec be enlarged to include maybe something
like an 'spf-helo' check which would be usable in the HELO ACL?

Comments?

Thanks,

Dan Mitton