[vilord]

What I would do is to use the ceregeditor program (not sure of link) which downloads the Registry to the PC via activesync connection, it can look for registry changes...

Then from the phone change the connection properties to auto-assigned and use the reg editor's compare function... it can tell you exactly what registry key is used to control auto or manual ip assignments.

Then you can either create two custom cab files that will turn on and off dhcp, or write a little program in c# that does the same thing. Cab files are easier, and there's tutorials out there somewhere to do it.

I don't know if it would work, nor will I do it for you, as I happily use dhcp and see no reason to use static IPs. Good luck and let us know if you have any success!