Hi, all I was compiling iptables-1.2.4-0.2 and i expirienced the following error. I'm using redhat 7.3, can someone help me? I downloaded the most version of autoconf, and the error continues, and i've looked for an updated rpm file for the kernel-headers, but i didn't find anyone. [root@xxxxxxx iptables]# make In file included from /usr/src/linux-2.4.19/include/linux/config.h:4, from /usr/src/linux-2.4.19/include/linux/netfilter_ipv4.h:8, from /usr/src/linux-2.4.19/include/linux/netfilter_ipv4/ip_tabl es.h:25, from include/libiptc/libiptc.h:6, from include/iptables.h:5, from extensions/libipt_dscp.c:16: /usr/include/linux/autoconf.h:1:2: #error Invalid kernel header included in user space Extensions found: IPv4:dscp IPv4:length IPv6:LOG IPv6:owner IPv6:limit IPv6:mac IPv6:multiport cc -O2 -DNDEBUG -Wall -Wunused -I/usr/src/linux-2.4.19/include -Iinclude/ -DNETF ILTER_VERSION=\"1.2.4\" -fPIC -o extensions/libipt_tcp_sh.o -c extensions/libip t_tcp.c In file included from /usr/src/linux-2.4.19/include/linux/config.h:4, from /usr/src/linux-2.4.19/include/linux/netfilter_ipv4.h:8, from /usr/src/linux-2.4.19/include/linux/netfilter_ipv4/ip_tabl es.h:25, from include/libiptc/libiptc.h:6, from include/iptables.h:5, from extensions/libipt_tcp.c:7: /usr/include/linux/autoconf.h:1:2: #error Invalid kernel header included in user space make: *** [extensions/libipt_tcp_sh.o] Error 1 Regards Alex