I have a multisite setup where I'd like to un-share a table. The table is authmap and I am getting db errors when the same username from separate sites logs in and has a different uid - it attempts to update the table entry for this user but errors because the uids don't match. I have the user table separate because I don't want a user with admin privs from one site to have the same privs on another.
If I simply change my settings.php and rename the table, the table isn't recognized by Drupal. How exactly does Drupal know which tables are prefixed as "shared." I thought it was all read from the settings.php, but perhaps I'm over looking something. Also, are there any other issues I'm not considering in un-sharing a table?

Comments
Answered My Own Question...
While I'm still not 100% sure what the authmap table does exactly, in order for a entry to be made in it, one has to be a new user (to the site). Since I was already a user, it didn't write en entry into the un-shared table. There doesn't seem to be any "secret" to unsharing a table - just create the new un-shared table and adjust your settings.php for that site.
you can safely share the user table.
you can safely share the user table... as long as you keep the users_roles seperate... since that's where users get their permissions.
http://groups.drupal.org/node/4247