Moodle-Mahara compatibility

Hello, I'm new to the Moodle Community and would be very grateful for some advice!

My institution is currently planning a VLE transition from Blackboard to Moodle and I have been tasked with finding out which version of Mahara is compatible with Moodle 2.5 as I have been informed that not all versions work seamlessly to create a single sign on.

Is this correct? And if so, could anyone tell me which version of Mahara we require?

Thanks!