yup, they've done it to me again. after having to reformat my laptop after a buggy driver in tiger, my data is now unreachable in leopard after i believed their claim to have leopard support.
sonnet is amongst the worst companies for producing drivers I have come across. I wish I had bought something else, but now I'm stuck with them at least for the timebeing - other potential upgraders beware, their drivers are buggy!!