Magento module setup - change product attribute to not required

How do you change an eav attribute properties during the installation of a module. Specifically, i want to change a product attribute from being to required to not required. I am currently merging the updated product attributes in the getDefaultEntities call in my modules setup but its giving wierd results. For example: ``` public function getDefaultEntities() { return array( 'catalog_product' => array( 'entity_attribute_collection' => 'catalog/product_attribute_collection', 'attribute_model' => 'catalog/resource_eav_attribute', 'table' => 'catalog/product', 'entity_model' => 'catalog/product', 'additional_attribute_table' => 'catalog/eav_attribute', 'attributes' => array( 'short_description' => array('required'=> false) ) ) ); } ``` Results in the short_description field loosing its Frontend Label