Attribute based Sorting in a custom Portal Navigation Hierarchy

When creating via xml customization a custom Navigation Hierarchy the resulting structure is automatically sorted alphabetically. There should be the option to apply a sorting based on an attribute maintained in all level of this hierarchy like Hierarchy No.

It is a request from NBG that ordered a custom Process Hierarchy and we delivered that but they say that it is essential it is displayed according to the values on the Hierarchy No attribute rather than alphabetically.

Pls do consider this development since it might be suitable for many customers.Kindest Regards