When I test this in WP 3.12, I can get the whole ext DB authentiation process to work in terms of plugin configuration - but I cannot resolve a strange problem...
When logging in as a new user (one that is in the ext DB but the WP user table) - after entering username/password and logging in the login screen reloads with an extra message below:
User registration is not available from this site, so you can't create an account or retrieve your password from here. See the message above.
and I have to login again.
Surely this is not working right ?
A new user should not have to login twice.
I am 99.9% there with my WP setup - except for this one small issue