I thought as far as barefoot shoes/trainers went, the idea was for them to not offer any support or as little as possible. They are just supposed to protect from sharp things and bad weather (say things like hail and slippery ground after rain) so as a result I doubt they'd offer your ankles any support at all.
On the plus side, many shoes can actually bring on ankle problems because they create a higher point for your ankle to keel over on and this can mean if you do fall on your ankle the injury is from a greater height and could be worse so barefoot shoes can help limit that.
The whole ethos of the barefoot shoe is to allow you to be more incontact and aware of the enviroment around you through your feet. You may find that as a result your less suprized by uneven ground or feel as unstable when you do meet uneven ground because with the barefoot shoes your toes are allowed a bit more control (or this is the idea) and so its a lot easier to stabilise yourself as a result if you are knocked off balance.
I hope that answers your question!
