[HyperDB] setup help

[Ari Newman]

Has there been any documentation written on how to setup HyperDB or  
troubleshoot issues? I'm trying to get it going but am not a php dev  
really.

I added the contents of db-settings.php to my wp-config.php and  
replaced wp-db.php in ~/wp-includes/ with the HyperDB db.php.

getting this:

Warning: array_key_exists() [function.array-key-exists]: The second  
argument should be either an array or an object in /usr/local/filtrbox/ 
apache2/htdocs/www/blog/wp-includes/wp-db.php on line 266

Warning: mysql_affected_rows(): supplied argument is not a valid MySQL- 
Link resource in /usr/local/filtrbox/apache2/htdocs/www/blog/wp- 
includes/wp-db.php on line 429

Fatal error: Call to undefined method wpdb::set_prefix() in /usr/local/ 
filtrbox/apache2/htdocs/www/blog/wp-settings.php on line 211

All I'm trying to do is use HyperDB to get WP to work in a master- 
slave environment (both DB servers are local). I don't have multiple  
locations. My assumption is that the problem is with the database  
definition since we aren't not supposed to need to touch the db.php  
file? Here's my string. (I have replaced my real username and passwords)

add_db_server('global', 0, 'iad', 1, 0,  '10.101.242.23:3306',   
'10.101.242.23:3306', 'fbox_blog', 'dbusername',        'dbpassword');

any help would be great - this is time sensitive...

-Ari