MM-SUS eMail to supplier Order Changed

We are using SAP SRM 7.13 SP04 in MM - SUS Scenario.

We have activated Business function SRM_SUCO_1 and Customizing Switch SRM_701_SUCO_NOTIF_FILTER to get supplier

informed in case of new and changed purchase order. In the supplier Profile check box for purchase order is marked.

Now we have the Problem that only for new purchase orders a mail will be generated and for changed not.

In the documentation you will find the following sentence: "Subscribe and unsubscribe to e-mail notifications regarding changes to a business document."

So changes should be included!

Any idea how to activate?

Many thanks,

Michael