In order to make the Oracle XE database work with IBM WebSphere Portal IWWCM there are a number of steps to perform.

1. Ensure that the database is accessible using the Oracle SID (see the early post Oracle SID!=Service name)
2. Next you will need to increase the number of proceses that can be connected to the instance, as there are a large number of connection pools set up by the system, which the database will need to support. The following command worked in my environment:

       ALTER SYSTEM SET PROCESSES=150 SCOPE=SPFILE;

3. After having performed these base setup commands and options, you can run the IWWCM migration scripts to migrate existing data.
4. To ensure that the connection pooling works correctly, you will need to grant the following privileges to public:

   1	grant select on pending_trans$ to public;

   1	grant select on dba_2pc_pending to public;

   1	grant select on dba_pending_transactions to public;

5. Finally, grant the following privilege to each user to which connections are made from the application server.

       grant execute on dbms_system to <user>;

After having performed these steps you will have an Oracle XE database that will work happily with IWWCM.

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