APEX

Hello.

I want to create a small APEX application that can configure asynchronous change data capture (distributed hotlog) on certain tables.
Basically, what the application should do is to simply create change tables. Everything else is set up as prerequisite.

My problem is that when I run the following script from schema apex_cdd (using sqldeveloper) , it works; but if I run it from my apex application by calling it when pressing a button as a pl/sql process, it doen't work.
------------------------------------------------------------------------
BEGIN
apex_cdc.enable_table_capture
( i_owner => 'staging_cdcpub',
i_change_table_name => 'g_changeTable',
i_change_set_name => 'Source_changeSet',
i_change_source => 'orcl01_cs',
i_source_schema => 'My_src',
i_source_table => 'G',
i_column_type_list => 'STARTDATE DATE,STATUS CHAR(1),NAME VARCHAR2(10),ENDDATE DATE,DESCRIPTION VARCHAR2(255),ID NUMBER(8,0),VALUE NUMBER(10,2)'
);
END;
-----------------------------------------------------------------------

If I look in the trace file, i see that the error is:
---------------------------------------------------------------------------
CDCdebug:in ChangeTable.java enableDisabledTriggers: ORA-06550: line 1, column 8:
PLS-00201: identifier 'SYS.DBMS_CDC_SYS_IPUBLISH' must be declared
ORA-06550: line 1, column 8:
PL/SQL: Statement ignored


oracle.jdbc.driver.OracleSQLException: ORA-06550: line 1, column 8:
PLS-00201: identifier 'SYS.DBMS_CDC_SYS_IPUBLISH' must be declared
ORA-06550: line 1, column 8:
PL/SQL: Statement ignored
-------------------------------------------------------------------------------

Other remarks:
- My procedure calls: sys.DBMS_CDC_PUBLISH.CREATE_CHANGE_TABLE.
- I gave the same rights that I gave for apex_cdc schema to flows_030200 and APEX_PUBLIC_USER schemas (just to see if it works), but it doens't.

Is APEX calling the procedure from another schema ?
Does anyone has an idea why this procedure crashes if called from APEX application, but works ok if called from the same schema APEX application runs on, but using SQLDeveloper ?


Any thoughts are appreciated.
Radian