call database procedure authorizations

Hello,

we are trying to call HANA STP from ABAP program with "call database procedure". We created a proxy as described in the following document:

http://www.sdn.sap.com/irj/scn/go/portal/prtroot/docs/library/uuid/f06342ec-60a0-3010-b8aa-9ece92ae0ee5?overridelayout=true

but when we try to execute the ABAP report we get ashort dump: DBPROC_SQL_ERROR insufficient privilages.

Which privilages do we need to use the proxy?

Thanks,

Amir