I can't use 1.0.1 without porting the libraries for the nRFnetwork and driver.
That porting consists in most cases of the change of a few include statements and in some cases a few search and replaces. Some bugs in the Ethernet-Library have been fixed meanwhile. I won't install an old IDE to track down old bugs. BTW: have you checked if there doesn't exist a new version of these libraries which is compatible with version 1.0+?