pfctl: DIOCADDALTQ: Invalid argument

[kestas . j . k]

Hello,

I'm trying to give a computer on my LAN priority when it accesses the
internet with NAT. However when I write what seems to be a valid queue
set which should do the job fine I get

# pfctl -f /etc/pf.conf
pfctl: DIOCADDALTQ: Invalid argument


Here is the queue section of my ruleset, if I remove these and
references to them pfctl accepts the rest without a hiccup:

altq on $int_if bandwidth 100Mb cbq queue { ether, nattraffic }
queue ether bandwidth 70% cbq
queue nattraffic bandwidth 30% cbq (default) { out_, in_ }
queue out_ bandwidth 64Kb cbq { out_me, out_others }
queue out_me bandwidth 80% cbq
queue out_others bandwidth 20% cbq ( default )

queue in_ bandwidth 128Kb cbq { in_me, in_others }
queue in_me bandwidth 80% cbq
queue in_others bandwidth 20% cbq ( default )


Also, it accepts priority based queues without a problem too, just not
class based.
I have all of these options in the kernel:
device          pf
device          pflog
device          pfsync
options         ALTQ
options         ALTQ_CBQ        # Class Bases Queuing (CBQ)
options         ALTQ_RED        # Random Early Detection (RED)
options         ALTQ_RIO        # RED In/Out
options         ALTQ_HFSC       # Hierarchical Packet Scheduler (HFSC)
options         ALTQ_PRIQ       # Priority Queuing (PRIQ)


Does anyone have any ideas on what "pfctl: DIOCADDALTQ: Invalid
argument" might mean? Let me know if you'd like further info.
Regards,
Kestas