How to use the 'BAPI_ALM_ORDER_MAINTAIN' with the method 'CREATETONOTIF'

Dear friends,

I want to create the PM order referenced by notification in the ABAP program. BAPI 'BAPI_ALM_ORDER_MAINTAIN' seems a good solution. In my R/3 version ECC6.0, there is the method 'CREATETONOTIF' can be used in the importing parameter 'it_methods-method'. However, when I used the bapi and filled in the method, it doesn't work. The bapi created a PM order but not referenced by the notification.

I think I filled in some wrong values in those importing parameters like 'objectkey'.

Can anybody give me some hint? Thanks!