As you are no doubt aware the JET driver only supports 32bit.

It also has been deprecated in favour of the ACE driver.

I've swapped the connection string to 'Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties=dBase IV' and it works fine on 64bit.

(Disclaimer: by "it works fine" I mean "I've briefly tried it and nothing obvious blew up" ;) )

Is there any chance you could impliment either the ability to switch between these two drivers or allow the user of your lib to provide thier own connection string?

We don't need this urgently since we've just compiled our own version of your code using this new connection string, but I thought you would be interested to know this works and it would be a nice feature for others :)

I'll add this the next time I update the library. Thanks for sharing that the ACE driver appears to work with shapefiles. 

That's ok.

I figured it would be useful for others :)

Added in changset fa3e2cf1f088.