ip masqaradeing on RH9 !

Hi there.
I am currently running an internet gateway with a small private network on a mandrake system, where everything works just fine.
I ve just installed RH9 on another gateway box wich would change the old gateway up for some reason.
My problem is however that RH9 wouldnt let both interfaces ext/int work at the same time.
Everytime i am about to use the external interface to browse the internet i have to shut both if down and reload the external to gain access to the outside.
Ip chains are emptied firewalling shut off the kernel modules meant to provide masq. are in place fw script is loaded.
Still no connection sharing!
The same happens without masquaradeing!
Anyone have a slightest whats wrong?
I ve also tried to debug the system, checked
all sys files on the mandrake box for differences but found none.
How can those interfaces be brought up to work simoultaniously without having to switch one down to use the other?
Thanks! maw@chello.hu