Re-purpose EAN-13 field

[amlsupport]

Hi, 

 

I'm trying to re-purpose the EAN-13 field but it's limited to 13 characters.

 

I've changed the value in PHPmyadmin ps_product & ps_product_attribute.

 

I've also changed the line in classes/product.php to be 'ean13' => array('type' => self::TYPE_STRING, 'validate' => 'isEan13', 'size' => 50)

 

But if I try to enter more than 13 digits, nothing else is added to the field when I edit a product in the back end.

 

What am I missing?