I am having problems with getting PIM-SM v2 multicast routing working under
Linux 2.4.20.
I think that I may be missing an obvious configuration step.

I have pimd running on several machines, which are also OSPF routers.
I have set up some default routes for multicast addresses, just to stop the
networking code complaining, though obviously these are not on all
interfaces.

A <-> B <-> C <-> D

Output from pimd -d all, shows that all of the machines are aware of each
other.

However, when I use mtrace from machine A
e.g. mtrace ipmachineD 224.0.1.10
then it fails.
Similarly, with other multicast applications such as VideoLAN.

Multicast routes handled by PIM are also not shown by ip route.

Any thoughts?
I have not seen much multicast work happening on Linux for a while, since
the days of Mbone.
Is this the case?
I want to run IPv4, so an IPv6 multicast solution doesn't help.

Regards

Andrew