TestBed:Multicast in Ipv6 Mobility Wireless Network

I wish to setup one test-bed with 1 multicast FreeBSD router, 2 Linux
HOSTAP Access Point and 1 Notebook act acts as Mobile Node with MIPL
1.0.

The problem I encounter is how I can set buffer into 2 access point (
this 2 access point are within multicast group for MN and will recv
multicast packet from multicast router in upper stream) so that when
packet arrival, access point can buffer it if mobile node not within
it coverage. When MN roam into the area cover by one of this access
point, the MN will recv all the multicast packet. When MN roam from 1
access point to another access point also the same domain, MN node
will send a packet's sequence to new access point, new access point
will forward the the rest of the multicast packet. So MN will continue
recv Multicast packet as long as roam within same domain even between
2 access point. How can I set on MN that when roam to new access
point, it will send multicast packet sequence to new access point so
that MN will continue recv packet when roam while not duplicate packet
occur.