SAP Message REBFRS003 - Syntax error in interface &1 (see long text)

Diagnosis
copied in part from message REBFRS001
The generated interface &V1& contains the following syntax error:
V2

System Response
For more information on the position of the error, perform the 'Check'function for interface &V1& using the Class Builder (SE24).

Procedure
Correct the template used or the settings in the class registry, andthen generate the interface again.