error: ip_tables.o init_module:Device or resource busy

[Steve <info@fabsurplus.com>]

I'd like to preface this mail by saying that if a little knowledge is a 
dangerous thing, then I am very dangerous....

I have recently installed redhat 9.0 over the top of RH V7.3 and then I 
upgraded to iptables 1.2.7a with a 2.4.20-18.9 kernel using apt-get.
When I try to do anything with iptables, I get the following error:-

*************************************************************
e.g. iptables -F
/lib/modules/2.4.20-18.9/kernel/net/ipv4/netfilter/ip_tables.o: 
init_module: Device or resource busy
Hint: insmod errors can be caused by incorrect module parameters, 
including invalid IO or IRQ parameters.
     You may find more information in syslog or the output from dmesg
/lib/modules/2.4.20-18.9/kernel/net/ipv4/netfilter/ip_tables.o: insmod 
/lib/modules/2.4.20-18.9/kernel/net/ipv4/netfilter/ip_tables.o failed
/lib/modules/2.4.20-18.9/kernel/net/ipv4/netfilter/ip_tables.o: insmod 
ip_tables failed
iptables v1.2.7a: can't initialize iptables table `filter': iptables 
who? (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.
******************************************************

Obviously (?), there is something wrong with either the kernel or 
iptables as I have installed it .
I need to get iptables working yesterday.
Can anyone tell me a no-brainer way to achieve this ?
Does my version of kernel work with this version of iptables ?
Do I have to go back to an earlier version ?
Whats the best way to get out of this mess ?
I remember for my dos days we used to do "format c:" in this kind of 
situation.

Thanks a lot,

Steve

Update: I installed iptables 1.2.8 from tar.gz: same problem.
Hence, either it's a hardware config. problem (?), or kernel is setup wrong.
I am now tring to recompile the kernel using v 2.4.22.
Any help would be much appreciated as I have little idea how to 
recompile a kernel and all I need is iptables working, I'd rather avoid 
all this kernel stuff...