How to store a (boxed) model to the database?

[Magnus W]

I had expected the code below to store the model data to the database, but all it does is insert a new empty row.

class Model_Comment extends RedBean_SimpleModel {
 public $message;
 public $something;
}

R::setup('sqlite:../data/slask.db');
R::nuke();

$b = R::dispense('comment');
$m = $b->box();
$m->message = 'Test';
R::store($m);

What am I doing wrong, and how can I get a boxed model to be stored? Even trying to store 

$m->unbox()

 wont work

[Magnus W]

If I run the below code, I'd expect that the model would get stored in the database, but it just inserts an empty row without the message.

class Model_Comment extends RedBean_SimpleModel {
    public $message;
    public $something;
}

R::setup('sqlite:test.db');

R::nuke();

$b = R::dispense('comment');
$m = $b->box();
$m->message = 'Test';
R::store($m);

How can I get RedBean to insert data from a Model instead of a Bean?

Even using 

\R::store($m);

won't work...