ipv6 router advertisement

I have a router/server running Mandrake 9.1 and am trying to configure it as
an ipv6 router. I have another mandrake 9.1 machine and a windows XP
machine connected which are both ipb6 enabled. I am using the following to
try and get the ipv6 router running:

# start ipv6
modprobe ipv6

# enable ipv6 forwarding
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding

#configure tunnel
#!/bin/sh
if ! [ -f /proc/net/if_inet6 ]
then echo "IPv6 is not installed!" 1>&2; exit 1; fi

ifconfig sit0 up \
&& ifconfig sit0 inet6 tunnel ::193.113.58.80 \
&& ifconfig sit1 inet6 add 2001:618:400::c389:7859/128 \
&& route -A inet6 add ::/0 gw fe80::c171:3a50 dev sit1 \
&& route -A inet6 add 2000::/3 gw fe80::c171:3a50 dev sit1 \
&& ifconfig eth0 inet6 add 2001:618:48a::/48 \
&& echo 1 > /proc/sys/net/ipv6/conf/all/forwarding \
&& echo 'interface eth0
{
AdvSendAdvert on;
MinRtrAdvInterval 3;
MaxRtrAdvInterval 10;
prefix 2001:618:48a::/48
{
AdvOnLink on;
AdvAutonomous on;
AdvRouterAddr on;
};
};' > /etc/radvd.conf \
&& echo "IPv6 configuration completed" || \
{ echo "IPv6 configuration failed!" 1>&2; exit 1;}

# start router advertisement daemon
/etc/init.d/radvd start

The part for the tunnel was provided by btexact who I have my tunnel with.

I can verify that router advertisements are being sent by running tcpdump
and they are being seen on the other machines (again verified by using
tcpdump).

IPv6 can be used on the router as I can use ping6 or lynx to navigate an
ipv6 website, but this cannot be done on the other machines. When running
ipconfig/ifconfig on the other machines, I only have a link scope address,
but no global address.

I had this working a few months ago, but it isnt working now, I must have
changed something on the router to make it stop. Does anybody know what I
am doing wrong? Here is an "ifconfig -a" from my router.
Thanks
Allan

eth0 Link encap:Ethernet HWaddr 00:08:C7:C0:FD:3A
inet addr:192.168.0.201 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: 2001:618:48a::/48 Scope:Global
inet6 addr: fe80::208:c7ff:fec0:fd3a/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:31156 errors:0 dropped:0 overruns:0 frame:0
TX packets:28261 errors:2 dropped:0 overruns:0 carrier:2
collisions:0 txqueuelen:100
RX bytes:22339751 (21.3 Mb) TX bytes:2881187 (2.7 Mb)
Interrupt:11 Base address:0x1020

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:595 errors:0 dropped:0 overruns:0 frame:0
TX packets:595 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:76467 (74.6 Kb) TX bytes:76467 (74.6 Kb)

ppp0 Link encap:Point-to-Point Protocol
inet addr:x.x.x.x P-t-P:217.41.128.200 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:22185 errors:0 dropped:0 overruns:0 frame:0
TX packets:24781 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:2006022 (1.9 Mb) TX bytes:21966962 (20.9 Mb)

sit0 Link encap:IPv6-in-IPv4
inet6 addr: ::127.0.0.1/96 Scope:Unknown
inet6 addr: ::192.168.0.201/96 Scope:Compat
inet6 addr: ::195.137.120.89/96 Scope:Compat
UP RUNNING NOARP MTU:1480 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

sit1 Link encap:IPv6-in-IPv4
inet6 addr: 2001:618:400::c389:7859/128 Scope:Global
inet6 addr: fe80::c0a8:c9/64 Scope:Link
inet6 addr: fe80::c389:7859/64 Scope:Link
UP POINTOPOINT RUNNING NOARP MTU:1480 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)