Hi list, when I try to compile the user-land applications of iptables 1.2.6a, it stops at extensions/libipt_ECN.c with the following message: extensions/libipt_ECN.c: In function `parse': extensions/libipt_ECN.c:51: `IPT_ECN_OP_REMOVE' undeclared (first use in this function) extensions/libipt_ECN.c:51: (Each undeclared identifier is reported only once extensions/libipt_ECN.c:51: for each function it appears in.) extensions/libipt_ECN.c: In function `print': extensions/libipt_ECN.c:82: `IPT_ECN_OP_REMOVE' undeclared (first use in this function) extensions/libipt_ECN.c:83: warning: unreachable code at beginning of switch statement extensions/libipt_ECN.c: In function `save': extensions/libipt_ECN.c:99: `IPT_ECN_OP_REMOVE' undeclared (first use in this function) extensions/libipt_ECN.c:100: warning: unreachable code at beginning of switch statement make: *** [extensions/libipt_ECN.o] Error 1 any idea what include file I'm missing? In #include <linux/netfilter_ipv4/ipt_ECN.h I can find a couple of IPT_ECN_OP_SET... there - but no IPT_ECN_OP_REMOVE. I tried kernel 2.4.5 and 2.4.24 fyi ... Cheers, Stefan !