WonderShaper/tc IP filtering

[kolaf]

I'm currently running firmware version 1.9.2.7-5a on a wl-500gx. I'm attempting to force a specific subnet into the low priority class. I have tried using the Wondershaper script as it is by adding the subnet with a subnet mask as a parameter after the outbound bandwidth. This does not seem to have an effect. Will also tried modifying the Wondershaper script to hardcode the filtering using the following command:

tc filter add dev eth0 parent 1: protocol ip prio 10 u32 match ip src 192.168.3.0/24 flowid 1:30

this did not have any effect either. There is still no traffic in the low priority class. I've tried filtering on a port instead, effectively forcing all web traffic into the low priority class, which worked. (This was just for testing purposes )

My final attempt was to use IPtables to mark the packets and then use the following, and to classify the packets with tc:

tc filter add dev eth0 protocol ip parent 1: prio 0 handle 6 fw flowid 1:20

But this command fails with the error message:
RTNETLINK answers: Invalid argument

I have now tried everything I can think of, so I would greatly appreciate any suggestions anyone might have. my problem is that a computer in another subnet than myself greediely uses all outbound bandwidth, seriously limiting the performance of all of the network traffic.

[kolaf]

Could it simply be that packet classification and queuing which is done by tc takes place after all the things related to masquerading and nat such that all source addresses axed to have the same as the external IP address of the router? I have done some testing and found that filtering on destination addresses seems to work, but source address filtering still does not. I'm not sure how I can solve this problem without getting the fwmark filter to work.