First Solution:

There are 2 options for this, as I found out.

You need to have the module sale_order_dates installed (basic module)

With the Openoffice Writer Plugin you can edit and create sales order documents to be printed.
(To do this follow instructions in OpenERP after installing it through Applications).

After Creating a Copy of your Original SO, you can edit it through OpenOffice Writer.

One option is setting it for the entire Sales order(3a), the other is per product line(3b).

1. When in editor mode press the "Convert Brackets to Fields" button in the openerp toolbar.
2. Then add "Delivery date" as tekst followed with "Add Field" (Place this accordingly to option 3a or 3b wherever you like)

3. a. o(Sales order) And Choose Commitment Date

   b. line (Sales order line) and choos Order Reference/ Commitment Date

4. Save and user the plugin to send the report to the server

Hope this helps you.

Second Solution is added a custom field and a custom view and then adding this custom field to the report.

1. Make sure you are logged in as the Administrator account or an account with the same rights.
2. Go to Settings -> Database Structure -> Model
3. Search for Sale.order
4. Add custom Field to Sales order by clicking on the "Edit" button, then scrolling down and click on the link "Add Item"
5. Give it the name you want ( e.g. x_scheduled_date). All custom fields start with x_
6. Fieldlabel is how you want it to show up on your custom view.
7. Then under heading "Properties" choose "date" as Field Type
8. Then Press Save. Your custom field is now created.
9. Now go to Settings -> User Interface -> Views and search for sale.order.form
10. Then after you press edit, you can position the date where ever you want by pasting this :
    <field name="x_scheduled_date"/> and then saving it.
11. Then you can use the same steps as in the First Solutions, only now you add the field x_"field name given in step 5)

If you have any more questions, please let me know and I will try to answer them!