sorry about it taking so long to get back to you. I noticed it still doesn't work after upgrading to fedora 6 and the newest kernel (at the time) so I thought I'd give your legacy driver a try (if you still have it) I'd love to have those 4 extra sata ports. Just a question with the legacy driver would the performance take a hit? I'd be using the ports to add more disks to raid arrays.
kernel version: 2.6.19-1.2911.6.5.fc6:
linux distro: fedora core 6 64bit
lspci -v output for marvell sata -
03:00.0 SATA controller: Marvell Technology Group Ltd. Unknown device 6141 (rev 01) (prog-if 81)