Make sure you've adjusted the DHCP server so it is NOT giving out addresses within the range of statically assigned addresses.
That said, you may want to consider eliminating static IP addresses from your network. They are a pain to administer (as you are learning). If you must have a fixed address for a device (server), use the "static lease" available in the Actiontec routers. This uses DHCP but gives the device the same IP address all the time.
Here's a thread from a while back that discusses how to setup a static lease:
http://forums.verizon.com/t5/FiOS-Internet/I-need-help-creating-a-static-IP-Adress/m-p/544047
Enjoy,
