Deletion of open lines

Hi

I must delete some lines from sales orders. The system has created delivery for most of the items in the sales orders but some items where out of stock. These are still open in the sales orders and must be deleted to prevent the system from creating a new delivery with only this item.

There is quite a few orders that have these open lines so now I wonder if there is a way of deleting all these lines in all of these orders without having to enter each single sales order one by one?

/ Henrik