Mirror driver for vista/win7.

Hi friends,
I am trying to write mirror driver for xp,vista and win7 but some where I have read, mirror driver is not supported to vista/win7 but with some twick we can achieve this, is it true? If yes please let me know which all things I need to take care for vista / win7. Currently I am using WDK mirror driver and trying to make changes into it.

Any help/suggestion will give great support.

Thanks
/sarbojit