Setting up IPv6 using provider provided ip addresses

Im currently running ipv6 using a 6to4 tunnel provide by SIXXS but now im trying to use the IPv6 subnet my provider has provided me but i can`t get it to work

Router1

Cisco 887VA-SEC-K9 running DHCP on Dialer0 and Static on VLAN1

Dialer0

 ipv6 address autoconfig default
 ipv6 unnumbered Vlan1
 ipv6 enable
 ipv6 nd ra interval 30
 ipv6 dhcp client pd solcon-ipv6 rapid-commit
 ipv6 mld query-interval 60
 ipv6 virtual-reassembly in

Vlan1

ipv6 address 2001:xxx:xxxx:4C00::1/64
 ipv6 enable
 ipv6 nd other-config-flag
 ipv6 nd ra interval 30
 ipv6 dhcp server
 ipv6 mld query-interval 60

Router2

Mikrotik Routerboard RB450G


IPv6 adresses

G 2001:xxx:xxxx:4c00::2/64                             WAN-BRIDGE       no 
G 2001:xxx:xxxx:4c01::252/64                           vlan140          yes

IPv6 Routes

1 S  ::/0                     2001:xxx:xxxx:4c01::1           1
2 X S  ::/0                     6to4-sixxs-nlhaa01              2
3 X S  ::/0                     2001:9e0:8501:4c00::1           1

When i switch back to sixxs everything works fine. I`m switching back by disabling the default route from the provider interface and enabling the default route to the sixxs interface. I also switch the corrosponding ipv6 adresses on vlan140. RA seems to be working fine on vlan140 using both ipv6 subnets.

Using my laptop connected on vlan140 i can ping the adresses on the VLAN140 interface, and the adresses on the WAN-BRIDGE interface. I can also ping the address on vlan1 of the cisco