Help for Create Vehicle Master Error "/DBM/CL_VEH_IOBJECT_VEHICLE===CP"

Dear all,

the system is EHP4+DBM7.0 ,   （A configuration is not perfect system），I want to know what is missing configuration, or a system bug? Thank you!

When i create a vehicle master data, the system show the abap error :

Short text

    No access possible via the 'NULL' data reference

What happened?

    Error in the ABAP Application Program

    The current ABAP program "/DBM/CL_VEH_IOBJECT_VEHICLE===CP" had to be

     terminated because it has

    come across a statement that unfortunately cannot be executed.

Error analysis

    There was an attempt to access a data object via a 'NULL' data

    reference (points to 'nothing').

    A data reference must point to data object before it can be used to

    access the referenced data object.

    The reference was either never set or it was set to 'NULL' using the

    CLEAR statement.

Trigger Location of Runtime Error

    Program                                 /DBM/CL_VEH_IOBJECT_VEHICLE===CP

    Include                                 /DBM/CL_VEH_IOBJECT_VEHICLE===CM00W

    Row                                     71

   68 *Convert the DBM API's multi-line extension data to

   69 *an iObject format

   70   ls_product-com_product-logsys = get_logsys( ).

>>>>>   ls_product-com_product-product_guid = lr_iobj_single_com->/dbm/v_vehicle-iobjguid.

   72

   73   CALL METHOD iobj_ext_multi_e2i

The system package level as :