interface FastEthernet0/0
 no ip address
 ipv6 nat
interface Serial0/0
 no ipv6 address
 ipv6 nat
interface Serial0/1
 no ipv6 address
 ipv6 nat
ipv6 nat v6v4 source list allAddr pool v6v4po1
ipv6 nat v6v4 pool v6v4po1 10.11.12.1 10.11.12.254 prefix-length 24
ipv6 nat prefix 2006::/96 v4-mapped allAddr
ipv6 access-list allAddr
 permit ipv6 any any