Like you see in the screenshot (first one) the duplex option works in OpenOffice.
The Screenshot of course was made on the same computer (else it makes no sense).
Because LibreOffice is based on OpenOffice that option was missed.
When you have also a look here at LibreOffice 3.5.0 into the printing dialogue:
Hello,
additional info now.:
Like you see in the screenshot (first one) the duplex option works in OpenOffice.
The Screenshot of course was made on the same computer (else it makes no sense).
Because LibreOffice is based on OpenOffice that option was missed.
When you have also a look here at LibreOffice 3.5.0 into the printing dialogue:
http:// www.glomme. de/snaggit/ 2012-03- 01_17-08- 52.snagproj. jpeg
you see nothing also in 3.5 will be changed.
In opposite of OpenOffice:
http:// www.glomme. de/snaggit/ 2012-03- 01_17-10- 54.snagproj. jpeg
or NeoOffice:
http:// www.glomme. de/snaggit/ 2012-03- 01_17-13- 05.snagproj. jpeg
you see there the duplex Options work. All programs are running on OSX 10.7.3.
At windows 7 the option is there also if it will be hidden:
http:// www.glomme. de/snaggit/ 2012-03- 01_17-39- 50.snagproj. jpeg <- Option
http:// www.glomme. de/snaggit/ 2012-03- 01_17-41- 09.snagproj. jpeg <- Duplex
So only here at osx (not tester here at linux) the option will be missed.