I can't execute an SP that calls another SP inside - response (5) by Fred

For CREATE / REPLACE PROCEDURE, the CREATOR must have permission to execute any DML statements within the procedure (including CALL).
But the OWNER (database in which the procedure is defined) must have those permissions for execution.
 
Other restrictions may apply depending on the SQL SECURITY option; details are in the SQL Reference Manual (DDL Syntax volume) under the topic for CREATE PROCEDURE.