So, as it turns out, an enterprising individual got a D-Link 530T running on Mac OS X using the driver put out by Syskonnect. The 530T uses the Marvell 88E0003 chipset same as the Syskonnect 95xx series. Yes, you could just order a Syskonnect card online instead of going through the trouble, but you can pick up a 530T pretty much anywhere and have an american company for warranty support to boot. As I have pointed out before, the 530T only costs $25 most places, so if you have a machine that doesn’t have gig-e, this is a great deal.
This should work also for the D-link 550T which is a 64bit PCI card and supports jumbo frames. It uses the Marvell 88E1000 chipset like the syskonnect 98xx series cards. The 550T is a lot harder to find in store fronts as it is more expensive, but again you have an american company to support it if it dies.