I'm using the Duemilanove and I want to use both interrupt pins. I have them connected to pull down resistors and switches connected to the 5v pin of the board. My problem is that the two pins, which I have configured as input pins, seem to output voltages with reference to ground. One outputs a constant .5v while the other outputs various voltages depending on the state of the first pin. This seems to mess with the interruption as I have them both set to interrupt when the input is RISING. Any help or insight would be much appreciated.