3.1 and altq

[johansz_(_at_)_free_(_dot_)_fr]

Hi all
I am experiencing a strange problem with altq mechanism:
I hope someone could help me to find the origin of this
and perhaps its solution

My altq.conf is a big file:
cat /etc/altq.conf|wc -l
    1035

so the line interresting me are :
from
conditioner xl1 s172_128.11 <tbmeter 128K 32K <pass><drop>>
to
conditioner xl1 s172_128.253 <tbmeter 128K 32K <pass><drop>>
and
from
conditioner xl1 s172.16.64.11 <tbmeter 64K 32K <pass><drop>>
to
conditioner xl1 s172.16.64.81 <tbmeter 64K 32K <pass><drop>>

if i type :
sudo altqstat -I xl1:
here is what i got 
altqstat: cdnr on interface _xl1 
actions: 
  pass:583069 drop:30954 mark:0 next:492668 return:0 none:0 

actions: 
  pass:584838 drop:31017 mark:0 next:493821 return:0 none:0 
[tbmeter: s172.16.64.81] handle:0xe08b9980 
  in:              0 pkts                0 bytes (0bps) 
  out:             0 pkts                0 bytes (0bps) 
[tbmeter: s172.16.64.80] handle:0xe08b9a80 
  in:              0 pkts                0 bytes (0bps) 
  out:             0 pkts                0 bytes (0bps) 
[tbmeter: s172.16.64.79] handle:0xe08b9b80 
  in:           5827 pkts          8323401 bytes (0.79Kbps) 
  out:           491 pkts           732145 bytes (0bps) 

none of 172.16.128 addresses are listed 
Can someone explain me why ?

FYI on the xl0 i have cbq rules 

and my /var/log/daemon just says:

Dec 17 16:30:23 outdoor altqd[2132]: ALTQ config file is /etc/altq.conf
Dec 17 16:30:23 outdoor altqd[2132]: tbr is already installed on xl0,   using 
the current setting (rate:100.00M  size:11.72K).
Dec 17 16:30:23 outdoor altqd[2132]: syscall error: add filter failed!: Invalid 
argument
Dec 17 16:30:23 outdoor altqd[2132]: can't add ctl class IPv6 filter on 
interface 'xl0'
Dec 17 16:30:23 outdoor altqd[2132]: conditioner attached to xl1
Dec 17 16:30:23 outdoor altqd[2132]: cdnr enabled on interface _xl1 (mtu:1500)
Dec 17 16:30:23 outdoor altqd[2132]: nop enabled on interface xl1 (mtu:1500)
Dec 17 16:30:23 outdoor altqd[2132]: cbq enabled on interface xl0 (mtu:1500)