NAT rules in ppp

[Warren]

This is the rule i presently have in my ppp.conf file  

nat port tcp 10.100.6.10:6881-6999 6881-6999

What im wanting to change without the need to use an actual FW is to have it 
so those ports are forwaded across my entire local subnet rather then a 
specific local IP.  Can this be done or am i limited to specific machine 
IP's ?

-- 
Yours Sincerely
Shinjii
http://www.shinji.nq.nu