Using a 3ware 9750-8i controller with a logical NTFS partition

I already have a NTFS partition in a Raid5 configuration, I can't move to another filesystem as I don't have the possibility to back up all the data. Is there a possibility to use the existing partition, I didn't find a possibility to add the partition to the system (the controller does show, so the drivers seem to work).

Greetz ChacalCH

I do know that, but there is no possibilty to move all that data to a new filesystem at the moment. I'd prefer ext4 as well, but I don't see how I can do that as there is no possibility to migrate without buying new disks.