juniper & md5 auth on bgp

Hi guys,

I've come across a strange problem while implementing MD5 auth on
bgp between a juniper (5.6R2.4) & cisco (12.1.9a) router. The bgp for
the juniper side is in a non-main routing instance. I've configured the
MD5 password on both routers, but the bgp can't be established. Following
the recommended resolution in this mailing list also didn't help either.

On the juniper router, the log shows a lot of these:
tcp_auth_ok: Packet from x.x.x.x:29594 unexpectedly has MD5 digest
last message repeated 3 times

On the cisco router, the log shows these:
%TCP-6-BADAUTH: No MD5 digest from x.x.x.x:2124 to x.x.x.x:179

The strange finding is the moment i move the bgp group to the main routing
instance, everthing works as per expected... Has anyone encounter similar
problem? What could be the cause?

Thanks,
Wei Keong