[Serusers] NAT problem with Ser 0.8.12, LinkSys and X-Lite

I moved ser from inside my office to a public IP address. When I use X-Lite it connects to ser, tries to login anonymously and ser sends back the Unauthorized packet. When it was in the office X-Lite would then send the name/password and login. It doesn't do that now. I'm using a LinkSys router. When the packet comes back to the LinkSys router from ser it hits the LinkSys at port 5060. I don't believe that's correct but I can't figure out how to correct it. I enabled nathelper but am not sure what to do next. Also, where is the documentation for the nat_uac_test? I can't find a single refererence to that in my source code anywhere. Bill