Rate issue while getting unit price to be used in sales order or purchase order from Trade agreement journal?

I have created multiple journals for an item(suppose “item1”) in AX2012 with multiple rates and different from and to date.

Like for Journal 1, From date is set as 1/12/2013 and to date is NULL and rate as 50.

for journal 2, From date is set as 7/12/2013 and to date is NULL and rate as 60.

Now, logically when selecting item in sales line form on or after 07/12/2013, i must get unit price 60. But unit price that i am getting is 50.

How to get latest price of an item a/c to from date in sales line form?

You must put an end date of 06/12/13 on the first line to deactivate it, otherwise it is a valid price to be returned.