I have read on the web that the version of Darwin included in OS X 10.1 is 1.4.1
When I type uname -r in a terminal window it returns 1.4 and not 1.4.1
Can anyone else see 1.4.1 returned in terminal in OS X.1 ?
But, the sources now available at www.apple.com/darwin do seem to match, well enough that the IOUSBFamily project I downloaded worked when I converted AppleUSBMouse to left-handed and installed it on my 10.1 system.
The binary distributions of Darwin and Mac OS X should always have different version numbers. This is to indicate that the kernels were built seperately, and may contain differences. Darwin 1.4 and Darwin 1.4.1 are very similiar, though 1.4.1 is missing some proprietary code that Apple cannot distribute for various reasons.