pppoe, dhcpcd v6 and renew

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

Hello,
my new DSL provider has an ipv6 setup which requires the client side
to send a Delegated Prefix request to get the NRA to route the ipv6 block
to the client.
I could do this with dhcpcd:
interface pppoe0
        noipv6rs
	ipv6only
	ia_pd 0
	ipv6ra_noautoconf
	nogateway
	nohook resolv.conf, hostname, ntp.conf
	noipv4

my router just needs to send a dhcp6 request or rebind, it doesn't need
to handle the reply (everything is static).

The problem is, if for some reason the pppoe session terminates,
the kernel will successfully initiates a new one but dhcpcd doens't send
a rebind, and the ISP stops routing my prefix. I have to manually
restart dhcpcd to fix this.
I tried ifwatchd but pppoe doesn't send events in this case.

I tried to add a 'leasetime 600' in dhcpcd.conf, in the hope that
dhcpcd would periodically send a rebind but it doens't happen.

Any idea how this could be properly fixed ?
I could periodically start dhcpcd from cron but I'd prefer a cleaner
way to achieve this ...

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--