Sigh which is why third party drivers are always such a pain!
Does eSATAII Rosewill RC-605 ExpressCard not work with 10.6? (external HDD question) – Mac Forums
Yes, the card presently doesn’t work. I’ve tried different variations of the Sil3132 driver but always get a kernel panic at startup (the original drivers were placed in the Incompatible Software folder when I installed Snow Leopard). At some point we’ll probably see new drivers from Silicon Image but I’m not holding my breath.