Okay so if you had a second ISP it could be done. Or how bout a second public IP from the same ISP???? Both of which are very typical when one is using CISCO or other higher end Routers (business case and business sense = requirements for multiple IPs and flexible routing).
2nd ISP should work fine. 2nd IP from same ISP should work too. I'm thinking creating new virtual WAN interface (i.e. wan1:1) and assign it 2nd public IP and go from there.
