Some missing changes for the $wgShared(DB|Prefix|Tables) setup:

Some missing changes for the $wgShared(DB|Prefix|Tables) setup:
* $wgCookiePrefix:
** Shared stuff should always come before local stuff when setting the cookie prefix (by my count, if you set $wgSharedDB and $wgDBprefix with the old order, even though your usertable is shared, your cookies would be local and logins wouldn't be shared right.
** Because the user table isn't always shared anymore, we only want shared code when $wgSharedTables has 'user' set inside of it.
** We now have $wgSharedPrefix, this should also be accounted for in the cookie prefix.
* updaders.inc: The logic for the $doUser test has changed since the conditions that the user table is shared has changed. Now when $shared is true we only want to $doUser when we have a shared database and 'user' is being shared, otherwise if $shared is false, we only want to $doUser when there is no shared database, or 'user' is not being shared.

Check MediaWiki.org's $wgSharedDB documentation for those on 1.12, I'll post a link there to a patch I maintain for 1.12.