Hello Giogio,
The hosts with Windows XP are in diferents Domains, but in the same Subnet. I've tried a ping from all host and don't have any problemes with the comunication.
I've tried search from automatic function and manual system (DNS) and the result is the same, the aplication doesn't can watch the computers.
The versión of Console is: 1.1.131.7, and the client versión is 6.0.1345. The version of OS is Winodws 2003.
Thanks for your help,