[Mediawiki-l] Can't setCookies() via hook to login user

[Brian Carpenter]

A few published autologin solutions, as well as
SpecialUserLogin::processlogin uses the $wgUser= $u followed by
$wgUser->SetCookies method similar to the below snippet to login an
existing user.

When running this as a hook function, the Cookies won't set (won't
login). Debug log shows $tmpuser->getID()=13 and
$tmpuser->getName()='John Smith' just prior to the $wgUser=$tmpuser
statement.

Cookies are enabled,

What else is needed?

Thanks for any input,
Brian
- - -

function AutoL(&$user)
{
        global $sso_UN,$wgUser, $wgCommandLineMode;

         if ( !$wgCommandLineMode && !isset( $_COOKIE[session_name()] ) ) {
            User::SetupSession();
         }

        //Cancel if session is current
        $tmpuser = User::LoadFromSession();
        if($tmpuser->isLoggedIn())
             return;

        //Is the user already in the database?
        $tmpuser = User::newFromName($sso_UN);

        //If exists, log them in
        if($tmpuser->getID() != 0)
        {
                $tmpuser->loadFromDatabase();
                $wgUser = $tmpuser;
                $wgUser->setCookies();
                $wgUser->saveSettings();
                return;
        }
}