Connect two asterisk servers

Hi ,
I want to connect two Asterisk servers with each other to dialogue
I like apply this example :
alkia.net/index.php/how-t…-Asterisk.html
how can i have two Asterisk servers on the same PC and connect them?
the first one under CentOS5 on Vmware , the second under Windows XP
Can you help me
thank you in advance for any help,

funny, if you can install centos-5.3 and virtualbox with asterisk server.