Braccio and ethernet shield not working together

Hi all,

I have a Arduino Uno, a Braccio Tinkerkit robot arm and a Ethernet2 shield.
I want to control the robot arm through the web server of the Ethernet2 shield.
When I connect both shields on the UNO, the web server fails to respond, but the Braccio still works when programmed directly.
When only the Ethernet shield is plugged onto the UNO, the web server works perfectly.
Are they incompatible together?
Are there sample sketches available for controlling the robot through web server?

Would be great if someone is able to answer this!
Best regards,

Frank