Default contact list of values

All Say we have 2 customers - A and B. When we setup a reciprocal relationship between the two customers and for either of the customer for selecting a list of vaules for Default Contact under Site Use details we get all the contacts that are defined for A and B However, when we create the sales order with Ship To Customer as A and Bill To customer as B, the contacts are restricted to the particular Site Ship Contact lov will only show the valid contacts from A (as it is the Ship To) Bill To Contact lov will