public function addConfig($config)
{
// make sure the config is compatible first
if (!$config instanceof $this->configType) {
throw new E4xx_IncompatibleConfigClass($this->configType, get_class($config));
}
// if we get here, then we're good to go
$name = $config->getName();
$this->configs[$name] = $config;
// keep the list sorted
ksort($this->configs);
}