intermittent issue ifconfig cannot assign link-local address

[STEPHEN JONES <smj%cirr.com@localhost>]

I'm seeing an issue with ifconfig failing in an unpredictable way which may be 
related to inet6.

For instance:

$ ksh network stop
Stopping network.
Deleting aliases.
Downing network interfaces: bge0 bge1.
$ ksh network start
Starting network.
Hostname: NetBSD
NIS domainname: NetBSD
IPv6 mode: host
Configuring network interfaces: bge0 bge1.
Adding interface aliases:.
add net default: gateway x.x.x.x

Works fine, but then doing the same command again:

$ ksh /etc/rc.d/network stop
Stopping network.
Deleting aliases.
Downing network interfaces: bge0 bge1.
$ ksh /etc/rc.d/network start
Starting network.
Hostname: NetBSD
NIS domainname: NetBSD
bge0: cannot assign link-local address
bge0: cannot assign link-local address
IPv6 mode: host
               Configuring network interfaces: bge0ifconfig: exec_matches: 
Invalid argument
ifconfig: SIOCSIFMEDIA: Invalid argument
 bge1.
Adding interface aliases:.
route: writing to routing socket: Network is unreachable
add net default: gateway x.x.x.x: Network is unreachable

And a basic ifconfig fails as well:

$ ifconfig bge0 inet x.x.x.x netmask 255.255.255.0 media 1000baseT mediaopt 
full-duplex
ifconfig: SIOCSIFMEDIA: Invalid argument
bge0: cannot assign link-local address
bge0: cannot assign link-local address

I have not changed the switch or with the physical interface, so it seems to be 
software issue.

The odd thing is that reboot a couple of times will allow the machine to come 
up as it should.

NetBSD 6.0.1 and 6.1_RC3