I am wondering the same.
We've just bought 6 servers with ICH9R chipset and licences for Window Server 2012. Unfortunately when we use the RAID drivers to install Windows Server 2012 it shows the Mirrored Drives separately. The mirror was created inside the Controller before any OS interaction and as far as the chipset is aware it has a mirrored array.
We could really do with a work around or a driver ,
how much longer do we have to wait for this?