It is pretty crappy that the 1.5x IDE that supports DUE doesn't include a few of the libraries
that come with the AVR like EEPROM and SoftSerial.
Paul's Teensyduino does come with support for these for his Teensy 3 ARM based products.
Yet another reason why I really like the Teensy products.
Paul has done a great amount of work to ensure backward compatibility with the AVR
based interfaces & APIs so often things "just work" with teensy that don't with other
products - including the official Arduino boards.
This includes handling many of the pre 1.0 to 1.0 library APIs that the Arduino team changed
which broke 100% of all the 3rd party library code and sketches that used them.
--- bill