tc filters and libpcap

Hi
I'm trying to use tc to shape traffic sent using libpcap (actually
tcpreplay, which is based on libpcap). I'm doing this for a research
project.

i have a simple prio scheduler with a default band 2:

tc qdisc add dev eth0 root handle 1: prio priomap 2 2 2 2 2 2 2 2 2 2
2 2 2 2 2 2

with two filters attached to it:

tc filter add dev eth0 protocol ip parent 1: prio 1 u32 match ip dport
80 0xffff flowid 1:1
tc filter add dev eth0 protocol ip parent 1: prio 2 u32 match ip dport
443 0xffff flowid 1:2

(don't mind the port numbers, they're here just for the example)

When sending actual traffic, the filters work and I see the
appropriate traffic entering the right class. BUT when replaying
captured traffic (with the appropriate port numbers) over eth0 using
tcpreplay, all packets end up in the default band 2 as if the filters
simply refuse to work.

Can anyone suggest a solution?

Thanks!