[FW1] Multiple links

[security]

Hi all,   We have Checkpoint firewall 4.1 setup as shown below                                  ISP---->Router------>NIC1 (External)----nat -----> NIC2 (internal)                                                         |                                                         |                                                  NIC3 DMZ                                                  web & mail servers on static nat     ISP leased line (HDLC)--->Router (serial port)-->Router Ethernet ports--> CP 4.1 Ext interface --->Internal NIC and DMZ NIC (Natted to Private zone & DMZ).   Now I have to add one more leased line to this setup for link redundancy. The second link will be taken from a different ISP which in turn assigns us with different pool of Valid IP addresses.   Could some one help me with information, who have setup or come across this sort of situation.   Thanks   Regs   sathish m r