XPS L401x, Windows 8, Secure Boot

I have upgraded to my PC from windows 7 to windows 8 pro without any problem. And it support all the feature except the SECURE BOOT this is due to firmware update & unfortunately dell is not providing any firmware update for windows 8 for XPS L401x. And when i asked dell to please provide firmware update,then they only say that this system does not support windows 8, So my question to dell if this system does not support then how i am able to upgrade this (xps l401x) system from windows 7 home premium to windows 8 pro without having any problem.But when i appeal for firmware update/driver for windows 8 to DELL (the customer care). they says that We will update the drivers and BIOS after our product team has confirmed that this system is compatible with XPS14 after series for test. I shall also share your post with them about your conversation with Microsoft. & on the next day got replay that "Just received an update that there would not be any drivers or BIOS for this system as its not compatible". Actually Dell did not do any test regarding this system. And they are not willing to provide the firmware update for their old product like XPS L401x. Because of there business policy. Non dell branded of old device (older than xps l401x series & with lower configuration compared to this) device get their firmware update to install new version of operating system like windows 8 but the DELL will not.