I'm trying to contruct an array from a class and it's many-many related object and I don't understand how to get the related many-many object part.

I have a class that has a many-many relationship with a dataobject.

class SomeClass extends Page {
	public static $many_many = array(
		'Categories' => 'Category'
	);
}

class Category extends DataObject {
	public static $belongs_many_many = array(
		'SomeClasses' => 'SomeClass'
	);
}

In another class I want to access both the parent and the related data to construct the array.

class MyPage_Controller extends Page_Controller {
	$foo = DataObject::get('SomeClass'...);
		foreach($foo as $bar) {
			$blah1 = $bar->MenuTitle;
			$blah2 = $bar->Content;
			$blah3 = $bar->Categories;
		}
		$myarray = array(
			"menu"=>$blah1,
			"content"=>$blah2,
			"category"=>$blah3,
		);
}

How do I get the many-many related Categories?
$blah3 = $bar->Categories;

Thanks in advance for any assistance!

UPDATE:
In my foreach statement, I include:

$mycategory = $product->Categories();

Which returns a ComponentSet. With that I can access my related object by running it through another foreach() statement:

foreach($mycategory as $category) {
    $somevar = $category->CategoryName;
}

Chris