dummynet log messages after recent update

Hello,

I recently upgraded my firewall from a soekris net4501 to a net5501.  As part of this process I update my freebsd sources to CURRENT as of 11/13/2009 1300 GMT.  Once the new box was up and running I noticed some odd output in the logs:

  Nov 13 18:30:19 gate kernel: dummynet: OUCH! pipe should have been idle!
  Nov 13 18:30:34 gate last message repeated 15 times

My dummynet configuration looks like this:

  fw='/sbin/ipfw -q'

  $fw pipe 10 config bw 950Kbit/s
  $fw queue 10 config pipe 10 weight 100
  $fw queue 20 config pipe 10 weight 1

  $fw add 6100 queue 10 tcp from any to any tcpflags ack iplen 0-80 out via $oif
  $fw add 6110 queue 10 udp from any to any iplen 0-80 out via $oif
  $fw add 6120 queue 20 tcp from any to any \{ not tcpflags ack or not iplen 0-80 \} out via $oif
  $fw add 6130 queue 20 udp from any to any not iplen 0-80 out via $oif

I am running SCHED_4BSD with a HZ of 1000.  Otherwise the kernel is mostly a stripped down version of GENERIC.  I can post the full config if it would be relevant.

I was previously running a HZ of 250, but I increased it to 1000 to see if that was causing the problem.  It did reduce the number of OUCH messages, but did not get rid of them completely.

Does anyone know what could cause these messages?  Should I be concerned?  As far as I can tell the network is working fine in spite of the log output.

Thanks.

- Ben