PostgreSQL cache table errors during upgrade from 4.7

I just upgraded from Drupal 4.7 to Drupal 5, and everything went smoothly except for the following persistent list of errors when running update.php:

    * warning: pg_query(): Query failed: ERROR: relation "cache_filter" already exists in database.pgsql.inc on line 125.
    * user warning: query: CREATE TABLE drupal.cache_filter ( cid varchar(255) NOT NULL default '', data bytea, expire int NOT NULL default '0', created int NOT NULL default '0', headers text, PRIMARY KEY (cid) ) in database.pgsql.inc on line 144.
    * warning: pg_query(): Query failed: ERROR: relation "cache_menu" already exists in database.pgsql.inc on line 125.
    * user warning: query: CREATE TABLE drupal.cache_menu ( cid varchar(255) NOT NULL default '', data bytea, expire int NOT NULL default '0', created int NOT NULL default '0', headers text, PRIMARY KEY (cid) ) in database.pgsql.inc on line 144.
    * warning: pg_query(): Query failed: ERROR: relation "cache_page" already exists in database.pgsql.inc on line 125.
    * user warning: query: CREATE TABLE drupal.cache_page ( cid varchar(255) NOT NULL default '', data bytea, expire int NOT NULL default '0', created int NOT NULL default '0', headers text, PRIMARY KEY (cid) ) in database.pgsql.inc on line 144.
    * warning: pg_query(): Query failed: ERROR: syntax error at or near "." at character 17 in database.pgsql.inc on line 125.
    * user warning: query: CREATE INDEX drupal.cache_filter_expire_idx ON drupal.cache_filter (expire) in database.pgsql.inc on line 144.
    * warning: pg_query(): Query failed: ERROR: syntax error at or near "." at character 17 in database.pgsql.inc on line 125.
    * user warning: query: CREATE INDEX drupal.cache_menu_expire_idx ON drupal.cache_menu (expire) in database.pgsql.inc on line 144.
    * warning: pg_query(): Query failed: ERROR: syntax error at or near "." at character 17 in database.pgsql.inc on line 125.
    * user warning: query: CREATE INDEX drupal.cache_page_expire_idx ON drupal.cache_page (expire) in database.pgsql.inc on line 144.
    * warning: pg_query(): Query failed: ERROR: relation "cache_content" already exists in database.pgsql.inc on line 125.
    * user warning: query: CREATE TABLE drupal.cache_content ( cid varchar(255) NOT NULL default '', data bytea, expire int NOT NULL default '0', created int NOT NULL default '0', headers text, PRIMARY KEY (cid) ) in database.pgsql.inc on line 144.
    * warning: pg_query(): Query failed: ERROR: syntax error at or near "." at character 17 in database.pgsql.inc on line 125.
    * user warning: query: CREATE INDEX drupal.cache_content_expire_idx ON drupal.cache_content (expire) in database.pgsql.inc on line 144.

I'm running Drupal in a PostgreSQL schema called "drupal" which is why the tables are prefixed with "drupal." I'm not sure why the "." is being rejected, but what's even weirder is the fact that the update.php file says this on line 694:

// If cache_filter exists, update is not necessary
  if (db_table_exists('cache_filter')) {
    return;
  }

So why is the script even trying to create the tables if it's supposed to return? I'm looking into it but help would by much appreciated.