SAP Message RLB121 - Maintainance of old Reuse Library no longer possible (see long text)

Diagnosis
The Reuse Library has been completely redesigned for Release 4.6C.
The data storage and presentation have been enhanced.
Unfortunately there is no automatic conversion from the old to the newstructure. Therefore you have to carry out the conversion manually.
To do this start transaction SLIBN. There is furtherinformation on creating and changing libraries in the application help.