IPv6 autoconfiguration fails

I recently reinstalled -current on my laptop and have started seeing
IPv6 autoconfiguration start failing.  I have two interfaces re0 and
ath0: re0 is plugged in and gets an address via DHCP while I'm not
using wireless at the moment so ath0 remains unconfigured.  However it
seems the IPv6 autoconfiguration tries to use ath0 instead of re0.
During boot I see:

re0: link state changed to UP
Starting Network: lo0 re0.
No ALTQ support in kernel
ALTQ related functions disabled
No ALTQ support in kernel
ALTQ related functions disabled
No ALTQ support in kernel
ALTQ related functions disabled
pf enabled
add net ::ffff:0.0.0.0: gateway ::1
add net ::0.0.0.0: gateway ::1
net.inet6.ip6.forwarding: 0 -> 0
net.inet6.ip6.accept_rtadv: 0 -> 1
get_llflag() failed, anyway I'll try
sendmsg on ath0: Can't assign requested address
sendmsg on ath0: Can't assign requested address
sendmsg on ath0: Can't assign requested address
add net fe80::: gateway ::1
add net ff02::: gateway ::1
IPv4 mapped IPv6 address support=NO
Waiting 30s for an interface to come up: ...........(re0)

ifconfig shows re0 having IPv4 and IPv6 link-local
addresses but no autoconfigured address, while I'm running rtadvd on
the router which is connected via re0.

-- 
Bruce Cran