[Asterisk-Users] newbie question

[MSL]

hi all,
its my first time to post here, im in the process of building asterisk 
based telephone system (just small). i already installed asterisk 
server, i just wanted to test 2 sip softphones to get working before i 
move on, is it possible to have 2 softphones talk to  each other without 
any cards?? (i.e. digium, just for testing purposes)
im using kphone, and i follow the instruction on how to configure it for 
asterisk, but there is a problem when i register the kphone, is there 
any configuration must follow before i make a calls using asterisk?? pls 
help.

THanks,
mike