Iptables seens doesn't understand network address not in class A, B or C

[caricand.jean-michel]

I have a local network with 10.0.2.0 address and 255.255.254.0 netmask.   My firewall have IP 10.0.2.130 on eth0. My station have IP 10.0.2.2. I configure my firewall for drop the ping from the station with 1 rules : # iptables -A INPUT -i eth0 -s 10.0.2.2 -p icmp -j DROP When I ping the firewall from my station (ping 10.0.2.130) , I receive an response from the serveur Why ?   What is the problem ? My netmask ?   If i modify my netmask to 255.0.0.0 on firewall and my station, the ping doesn't work. Normal !   Iptables don't understand network address not in class A, B or C    HELP ME !!!