pf+altq for bandwidth management

[Lan Tran]

Hello,

Is pf and altq a right combo for bandwidth limiting?  What I'm trying to do 
is limit each IP or block of IPs to predefined bandwidth.  I'm not doing 
traffic shaping, just wanting to prevent servers from hogging all the 
bandwidth.

My setup is as follow:
LAN {test server} -> xl1 {FreeBSD} xl0 -> router -> net
xl0 and xl1 are functioning as a bridge.  kernel has pf and altq compiled.

pf.conf:
ext_if = "xl0"
int_if = "xl1"
pc = "any"
set loginterface $ext_if

# to net
altq on $ext_if cbq bandwidth 100Mb queue { std_ext, test_ext }
queue std_ext bandwidth 3Mb qlimit 1000 priority 5 cbq(default red ecn)
queue test_ext bandwidth 2Mb priority 1 cbq(red ecn)

pass out on $ext_if from $pc to any keep state queue test_ext
---
The problem I'm having is that all outbound traffic from "test server" 
always shows around 3Mb instead of 2Mb per queue test_ext ruleset.  What am 
I missing?

Thanks,
LT