Description:
------------
I've never seen any discussion regarding the addition of a 
ReflectionParameter::getDocComment() method.

The only mention I've found is in this post from 2005(!):
http://news.php.net/php.internals/14906

This would be a very useful feature for dependency injection frameworks.

For example, if you want to use annotations to configure dependency injection on 
the following class:

class Service
{
    public function __construct(PDO $pdo, $configuration)
    {
    }
}

You would need to do something like:

class Service
{
    /**
     * @InjectParam(name="pdo", value="database.connection")
     * @InjectParam(name="configuration", value="database.configuration")
     */
    public function __construct(PDO $pdo, $configuration)
    {
    }
}

Whereas we could benefit from the following approach:

class Service
{
    public function __construct(
        /** @Inject("database.connection") */ PDO $pdo,
        /** @Inject("database.configuration") */ $configuration)
    {
    }
}