Testing netfilter rules

Hello List,

i would like to test my netfilter firewall. I am currently using ftester (http://dev.inversepath.com/trac/ftester) but i am not happy with that tool. Has anyone got some alternatives? I want a client/server or slave/master to test my open ports.

Nmap, netcat or telnet does not do the job since i need to have something to listen at the other end. (with hundreds hosts and ports)

Is anyone using ftester or something similar?
As far as i can tell ftester does not make a valid tcp handshake, it just fakes it.

My aim is to check if my needed/wanted ports actually are allowed.

Thanks, Mario