To change the Sales Order status as 'Partial Delivered'

Hi all,

I want to display SalesStatus as Partial Delivered if it is a partial delivery.

As we know Sales status field will show the lowest status of sales transaction.

But if it is a partial order i want to change this status (only in form) as Partial Order rether than Open Order.

Can anybody tell me how can I do this in AX 2009?

Regards