The Mint 14 kde 64 bit version will not print in duplex to my brother hl4150cdn printer. The printer is set to duplex (long edge) in the cups config page, and shown in the printer configuration page of the kde system settings. However, when I try to print from an application such as kate, kwrite, okular, libre office, etc., the duplex setting is ignored. On the application's print dialog, the printer properties show that long-edge duplex is indeed selected, but the duplex menu under the options button options tab is grey and unavailable (this may be bug 311656 in KDE). Regardless, there is NO WAY TO PRINT DUPLEX.
This is a definite bug, because all the hardware and network connections this machine is connected to worked with the previous OS (Debian squeeze kde -- no gnome) and there was no problem at all with printing in duplex from okular, kwrite, etc, or changeing the settings in their respective print dialogs. The Mint install is a clean install on a new hard drive. Now there is no duplex printing.
This is a real problem. Mint is costing me money by crippling critical equipment.