ip_conntrack_ftp and ip_nat_ftp module problem

Hi Kernel guys!

I'm running a 2.4.20 (i686, configured with "make menuconfig") and I have the following problem:

If I compile into the kernel ip_conntrack module, and its ftp and irc extensions, I can't insert ip_nat_ftp because it "can't find ip_conntrack_ftp module". If I want ftp nat and connection tracking, I have to compile ip_conntrack_* as modules because it seems that ip_nat_* are always compiled as modules instead of being compiled directly into the kernel when requested to do so, like ip_conntrack_*.

I think it's only a makefile problem. Can you fix it for 2.4.21 ?? I see "CONFIG_IP_NF_NAT_IRC=m" in config file, but that line doesn't exist in menuconfig.

Thank you very much.

PS.
Another question:

To have a working FTP or IRC NAT and connection tracking, I have to insert their modules (*_ftp and *_irc) manually with insmod or modprobe. lsmod tells they're usage count is always 0, even if they "work". Why can't those modules be automagically probed when required, like every other module, for example when I add a nat or a state rule with iptables? This inserts ip_conntrack, but not ip_conntrack_* and ip_nat_*. And with their usage count = 0, there's a risk that rmmod -a removes them.

Stefano from Rome