I'm trying to install ulogd tool in my system. ulogd requires nfnetlink_conntrack subsystem in the kernel. It seems nfnetlink_conntrack is not available in the Linux version(RHEL5) that I'm using. How to get that in my system? I can not find any info on this in Google, other than I get a bunch of results that give a link to the source code.
Recompile your kernel to enable it: