LARTC - Jan 2006 - how can I delete filter : RTNETLINK file doesn''t exist

what is the script for deleting filter that already exist???

the htb script is:

tc qdisc add dev eth0 root handle 1:0 htb default 4
tc class add dev eth0 parent 1:0 classid 1:1 htb rate 500kbps ceil 500kbps

tc class add dev eth0 parent 1:1 classid 1:2 htb rate 300kbps ceil 300kbps
tc qdisc add dev eth0 parent 1:2 handle 12:0 pfifo

tc class add dev eth0 parent 1:1 classid 1:3 htb rate 150kbps ceil 150kbps
tc qdisc add dev eth0 parent 1:3 handle 13:0 pfifo

tc class add dev eth0 parent 1:1 classid 1:4 htb rate 50kbps ceil 50kbps
tc qdisc add dev eth0 parent 1:4 handle 14:0 pfifo

when IP x.x.x.x access the web server (i.e http://test.com/class-A.php)
he get the filter to class A (flow 1:2) because in class-A.php there
is a script:
tc filter add dev eth0 protocol ip parent 1:0 u32 match ip dst x.x.x.x
flowid 1:2

then i wanna delete the filter for ip x.x.x.x so he get the default class (1:4)
when i exec as root:
tc filter del dev eth0 protocol ip parent 1:0 u32 match ip dst x.x.x.x
there are a feedback ---> RTNETLINK file doesn''t exist

anyone can help me???