> When I enable 1:1 NAT using a public IP
> as the external

	The docs say rather clearly that an IP on the Server NAT page is required:

http://doc.m0n0.ch/handbook/nat-1to1.html
"Forwarding traffic for additional IP adresses (also known as Virtual IP addresses) that are not the
IP address of the WAN interface is possible by first listing these IP addresses in the Server NAT
window. Then 1:1 NAT is used to redirect traffic for these IP addresses to internal servers."

...however m0n0wall 1.3 will not let a 1:1 rule be set up if the address is in use on the Server NAT
page?  I get:

"The following input errors were detected:
    * A server NAT entry overlaps with the specified external subnet."