Vista - Network connection properites do not persist across a reboot.

Im having trouble with my ad hoc wireless setup. On my Vista system I am
sharing a Broadband connection with a wireless home connection. When I do
this , the wireless conection will have DHCP disabled and an address of
192.168.0.1. The other systems conncected have DHCP enabled. All works fine
when I do this. I can share the connection and exchange files fine.

I reboot or power down the Vista system. When I power it back up, DHCP is
now enabled. My home network no longer functions. In addition, the broadband
connection is still shared with the home wireless connection. On the home
wireless connection, I disable DHCP and set the IP address as above and it
starts working again. Why doesnt the TCP/IP settings of the wireless
connection persist across a reboot.