DuinoOS is really FreeRTOS for Arduino AVR boards. I don't think there is a version for ARM and I believe DuinOS for AVR is based on an old version of FreeRTOS.
I have configured the latest version of FreeRTOS for AVR and ARM Arduino. It is located here FreeRTOSBeta20121215.zip http://code.google.com/p/beta-lib/downloads/list
I will be posting an update in a few days with the 16 examples from the book "Using the FreeRTOS Real Time Kernel - a Practical Guide". The examples run as Arduino sketches.
I also will include four other examples.