cannot use multicast ICP

Greetings,

I have a machine which cannot send/receive multicasted ICP requests.
Machine's OS is SunOS 4.1.4, and with Squid 1.1.7.
Other machines join the multicast session successfully, but only the
machine cannnot. There are no logging by squid. So I don't know what
should I do.

But one hint. I tried Squid 1.1.5, even the machine cannot send/receive.
But a cache.log says:
97/03/03 01:02:42| Detected DEAD Parent: 239.133.*.*/3128/3130
97/03/03 01:02:43| Detected DEAD Parent: 239.133.*.*/3128/3130
97/03/03 01:02:43| Detected DEAD Parent: 239.133.*.*/3128/3130
...

What does it mean? The other machines join 239.133.*.* successfully.

Sorry for my bad english.
Regards,

----
Kenichi Matsui
Graduate Student at TOHOKU Univ. JAPAN
phone://+81-22-217-7140
fax://+81-22-263-9306
mailto:matsui@nemoto.ecei.tohoku.ac.jp
http://www.nemoto.ecei.tohoku.ac.jp/~matsui/