telecastle,
I'm not seeing a .kext any where in the Mac OS X Drobo Dashboard 2.3.5 download. Nor do I see an included bundle that has one either. I'm gonna continue to look in to the package, but my first impression is that there isn't a specific drobo driver included. It may just use a generic USB Storage driver, which most OS's already have..I'll post again if I find anything to contradict this idea. I can't really say how it would work via thunderbolt, but I'm looking to see if other vendors require a driver for their thunderbolt attached drives. Seagate at least doesn't seem to provide a driver for their thunderbolt attached drives. (And I could just be 100% wrong and looking in the wrong place.)
At least now I'm curious.. Lol