Try to place the 12 pentominoes inside the largest possible rectangle, in such a way that the pentominoes divide the rectangle in 5 parts of equal size.
There may not be more then 5 open areas; also open areas are not allowed to touch each other in a corner.
The pentominoes must form one shape, so that from any pentomino there is a pentomino path to any other pentomino.
Find the largest solution in which two of the open areas is a rectangle.
 

The parts in our example are 36 squares.
Our rectangles are even squares!

We recieve a solution from:

Name	Country
Class 2B -KSO Glorieux (42)	Belgium

After a little searching we found a solution with three rectangles.  Can you do better?