[Freeswitch-users] How to Update external IP address on Ubuntu?

Hi, We are newbies to Ubuntu and Freeswitch. We have Freeswitch installed on Ubuntu with Auto-Nat and it works great. The issue we have is that our ISP only provides Dynamic IP's which do not change that often but when they do everyone goes into panic mode until we remember that by simply re-booting the server everything comes back to normal. My question: Is there a method we can put in place that would automate the external-IP update without having to reboot the server. Can Freeswitch notice that the external IP has change and reset itself without manual intervention? And if we need to reboot the server is there a program that would do this automatically when the external IP changes? Thanks cjb