Using 6 axis accelerometers I've been messing around with accelerometers for Arduino for a school project. I bought the SODIAL GY-521 accelerometer + gyroscope module for Arduino. It uses de Invensense MPU 6050. I managed to connect it onto my board and successfully detect it, but it returns values of -1 on all output ports. I was expecting there to be a port for every axis of acceleration and rotation but it seems that this isn't the case. How should I connect the module into my Arduino, and how should I program the Arduino to read my data?

I tried to follow the Arduino Playground example but the result was as explained above.

Thank you for all answers.
From the Arduino playground:
This sensor board has a voltage regulator. When using 3.3V to the VCC the resulting voltage (after the onboard voltage regulator) might be too low for a good working I2C bus. It is preferred to apply 5V to the VCC pin of the sensor board. The board has pull-up resistors on the I2C-bus. The value of those pull-up resistors are sometimes 10k and sometimes 2k2. The 2k2 is rather low. If it is combined with other sensor board which have also pull-up resistors, the total pull-up impedance might be too low.