> > It seems there is only an IPv6 version of pimd in pkgsrc. Is there a
> > reason for that?
> 
> My guess it's because there's no IPv4 PIM support in the kernel :)

Main reason is due to the code maintenance.
pimd had been maintained by USC/ISI even after the first release. And
the maintenance is now almost finished, even though some major bug fix
might be dealt with (if you send the report to the author). But no
enhancement will be done. In fact, pimd is RFC2367 base. This is also
the reason to stop the maintenance. 
On the other hand, pim6?d has been maintained by KAME after the first
release. Since there is no other free multicast routing protocol
daemon for IPv6 at this moment, KAME has been greatly collaborated the
tough work.

Actually, KAME has been maintained pimd because of some reason. But it
must confuse users that there are two release (original pimd and KAME
version pimd), so I personaly cannot recomend to use either one,
except for your test purpose or for your play. :)
Just FYI, as a new implementation, Xorp would be interested. But keep
in your mind it's pretty new.:) I believe Xorp does not oblige the
kernel modification, while it would help PIM Register message
encapsulation etc. via new APIs.
--
Hitoshi Asaeda