ipv6 configuration problem

I've tried to configure the ipv6 adress for my NIC but while everything seems ok I still can't ping6 the adress.

The module is loaded
$ lsmod | grep ipv6
ipv6 235233 12

and I've got site adress added to eth0
$ ifconfig eth0 | grep 'inet6'
inet6 addr: fec0::1/64 Scope:Site
inet6 addr: fe80::20f:1fff:fe78:d18/64 Scope:Link

looking into
$ cat /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=garfield
NISDOMAIN=mydomain.com
NETWORKING_IPV6=yes

but still when I do
$ ping6 fec0::1/64
unknown host


Why? What's wrong? Even specifying interface with ping6 -I eth0 doesn't work. Same results I've got with traceroute6.
Looking into ipv6 routes, there are some and they look fine.

I'm using FC3 with
$ uname -r
2.6.9-1.681_FC3smp

could ping6 fec0::1 or ping6 -I eth0 fec0::1 works?