Restricting Edit of Attribute Sets against a BP

Hello All,

I have a requirement to be able to restrict the editing of Marketing Attributes against a BP. 

The scenario is this.  SAP CRM receives BP from an external system via an interface.  Part of this interface delivers some marketing attributes.  The attributes in this set must not be editable in SAP CRM.  I have investigated the use of authorisation objects BGRKP and BGRKL, but these only control the ability to maintain the attribute set data, as far as I can see, and not to control how the attributes are handled at the BP level.

Any help greatly appreciated.

Many thanks

Jon