Mac eSATA cards...

I was interested in the Drobo S, I currently run the FW800 model, for my Mac Pro in which I run a FirmTek SeriTek/2SE2-E card. I was stopped in my tracks when I saw this card is explicitly listed as non-compatible with the S’s eSATA. Any word on what the issue is and when it could be expected to be resolved, if at all? Changing the card is not an option as I need it for another enclosure and don’t want to mess with other cards/drivers when things are stable the way they are. I know the S will run FW800 and be somewhat faster than my older Drobo but I can’t see buying something that doesn’t work to its fullest not knowing if the other issue will be resolved.