Order Items are associated with neither requirements nor productions runs created by mrp events of type sales order shipment

[Christian Carlow]

Order Items are missing from Order -> Requirement -> Orders tab of 
requirements created by MRP events of type Sales order shipment.  
Because they are missing, production runs created by requirements when 
approved also lack order item association.  After approving the 
requirement, I expected to see the production run created linked to 
order that caused its creation such as what happens for Configurable 
Goods and Marketing Packages.  Is there a reason order item associations 
to requirements and production runs created by mrp events should not be 
implemented in a similar manner as those product types?