Hi again,
more information:
*the IP address is not used. I've tried with a ping.
*I change the ethernet cable.
*when I connect the board I ping it and it responds.
*My operating system is Ubuntu 11 and since a week I 'm using arduino 1.0 IDE. So I erase the 022 ide version. I thought that maybe the libraries were causing some conflits...
I do not know what is the problem. Maybe you know basic tips I didn't realize.
Thank you!