Picking from invoice

Currently is possible to generate invoice from picking in suppliers and clients section.
We use some programs that it is possible to create the picking and the stock moves by a check mark in the invoice form.
I think that for supplier invoices would be very helpful. Especially when the purchase was not generated by openERP, and the invoices contains hundreds of items that needs to go to stock. One must do double work to receive and to invoice those items.
Also for customer invoices, if without any sales order, one needs to invoice and ship many items it has to double work to create invoice and delivery order.