Local Shared Object and IPv6

When I store a local shared object using IPv4 on a particular site I am developing, I don't get the Flash Player Settings dialog asking for permission. It just stores it seamlessly to the user.

BUT, when addressing the same site using IPv4 and trying to store the same local shared object, I get that Flash Player Settings dialog asking permission to store the shared object. The ip address in the dialog's message is also URL-encoded, so to the average web user, it would probably scare them and they would Deny access.

Why am I getting that permissions dialog? I must not know enough about how permissions work for the local shared object.