asterisk users - Apr 2005 - SIP phones to Asterisk using MAC address instead of IP address

Hi,

I know this can be done but I guess I am not understanding the few notes 
I have seen on this - can SIP phones be tied to Asterisk using a PC mac 
address instead of their IP address (obviously I am using DHCP). If 
someone could please point to the right Wiki or How to I would greatly 
appreciate it.

Thanks