function upgrade_290() {
	global $wp_current_db_version;

	if ( $wp_current_db_version < 11958 ) {
		// Previously, setting depth to 1 would redundantly disable threading, but now 2 is the minimum depth to avoid confusion
		if ( get_option( 'thread_comments_depth' ) == '1' ) {
			update_option( 'thread_comments_depth', 2 );
			update_option( 'thread_comments', 0 );
		}
	}
}

/**
 * Execute changes made in WordPress 3.0.
 *