relayd: pfe_route: failed to add gateway 22 Invalid argument

Hello,

I'm trying to use the relayd router function to add host routes to the routing
table with a route label for further processing by bgpd. The host ist directly
connected to the firewall.

relayd.conf:

table <service_v6> { 2001:xxxx:xxxx:xxxx::4 }
router "service_v6" {
route 2001:xxxx:xxxx:xxxx::4/128
forward to <service_v6> port 80 check tcp
rtlabel geo_service
}

fw1# relayd -vvvd
startup
socket_rlimit: max open files 1024
pfe: filter init done
socket_rlimit: max open files 1024
socket_rlimit: max open files 1024
socket_rlimit: max open files 1024
parent_tls_ticket_rekey: rekeying tickets
hce_notify_done: 2001:xxxx:xxxx:xxxx::4 (tcp connect ok)
host 2001:xxxx:xxxx:xxxx::4, check tcp (0ms,tcp connect ok), state unknown ->
up, availability 100.00%
pfe_dispatch_hce: state 1 for host 1 2001:xxxx:xxxx:xxxx::4
sync_routes: router service_v6 route 2001:xxxx:xxxx:xxxx::4/128 gateway
2001:xxxx:xxxx:xxxx::4 up priority 0
hce_notify_done: 2001:xxxx:xxxx:xxxx::4 (tcp connect ok)
pfe_route: failed to add gateway 2001:xxxx:xxxx:xxxx::4: 22 Invalid argument
hce_notify_done: 2001:xxxx:xxxx:xxxx::4 (tcp connect ok)
hce_notify_done: 2001:xxxx:xxxx:xxxx::4 (tcp connect ok)
hce_notify_done: 2001:xxxx:xxxx:xxxx::4 (tcp connect ok)


The route with the route label never pops up in the routing table. With IPv4
addresses the setup works as expected.

Any suggestions?