protected function seed($slug)
    {
        $package = $this->packages->where('slug', $slug);

        $className = $package['namespace'] .'\Database\Seeds\DatabaseSeeder';

        if (! class_exists($className)) {
            return;
        }

        // Prepare the call parameters.
        $params = array();

        if ($this->option('class')) {
            $params['--class'] = $this->option('class');
        } else {
            $params['--class'] = $className;
        }

        if ($option = $this->option('database')) {
            $params['--database'] = $option;
        }

        if ($option = $this->option('force')) {
            $params['--force'] = $option;
        }

        $this->call('db:seed', $params);
    }