Possible to have two I2c connections on 1 mega?

Im looking to incorporate this RTC into my project http://www.adafruit.com/products/255 It says that it uses an I2c connection to operate. I am already looking in to having two arduinos communicate through an I2c channel. I was wondering if it would be possible to have this RTC operate on the same board with a preexisting I2c connection. Thank you.

Yes,

With limitations http://forum.arduino.cc/index.php?PHPSESSID=r5p1j98c2g6qn20mm5frot7nv1&topic=120465.msg906701#msg906701

Maybe just use one of the 3 serial usarts to do cross-comms?