I've forgotten how this works.
In 1.0.1 the [libraries] folder has [Ethernet] included.
In 1.5.2 the [libraries] does not have [Ethernet]
but in 1.5.2 it APPEARS to me that the previous version's [libraries] folder has been moved to the [hardware-arduino-avr-] and same for [-sam-]
Is this line of thought correct ?
Has compiler libraries localities changed between the 2 versions ?
Maybe I'm having a grey moment ...............