JUNIPER provides the following IPv6 multicast features in its current release:

Main features (JUNOS 6.0):

  MLD version 1
  MLD version 2
  PIM DM/SM
  PIM SSM
  RP functionality (except encap/decap PIM register)
  Static RP configuration
  Multicast scope boundaries
  Static IPv6 Multicast routes
  IPv6 Multicast address family support on MP-BGP4
  IPv6 in IPv4 tunneling

Documentation: http://www.juniper.net/techpubs/software/junos/junos60/swconfig60-multicast/frameset.htm