Oracle + dbunit gets AmbiguousTableNameException

I am using dbunit to create database backups, which can be imported and exported. My application can use several database engines: MySQL, PostgreSQL, SQLServer, H2 and Oracle.

All of the above work fine with the following code:

            // Connect to the database 
        conn =BackupManager.getInstance().getConnection();
        IDatabaseConnection connection = new DatabaseConnection(conn);
        InputSource xmlSource = new InputSource(new FileInputStream(new File(nameXML)));
        FlatXmlProducer flatXmlProducer = new FlatXmlProducer(xmlSource);
        flatXmlProducer.setColumnSensing(true);

        DatabaseOperation.CLEAN_INSERT.execute(connection,new FlatXmlDataSet(flatXmlProducer));  

But on Oracle I get this exception:

!ENTRY es.giro.girlabel.backup 1 0 2012-04-11 11:51:40.542
!MESSAGE Start import backup
org.dbunit.database.AmbiguousTableNameException: AQ$_SCHEDULES
    at org.dbunit.dataset.OrderedTableNameMap.add(OrderedTableNameMap.java:198)
    at org.dbunit.database.DatabaseDataSet.initialize(DatabaseDataSet.java:231)
    at org.dbunit.database.DatabaseDataSet.getTableMetaData(DatabaseDataSet.java:281)
    at org.dbunit.operation.DeleteAllOperation.execute(DeleteAllOperation.java:109)
    at org.dbunit.operation.CompositeOperation.execute(CompositeOperation.java:79)
    at es.giro.girlabel.backup.ImportBackup.createData(ImportBackup.java:39)
    at es.giro.girlabel.backup.handlers.Import.execute(Import.java:45)

From the docs:

public class AmbiguousTableNameException extends DataSetException

This exception is thrown by IDataSet when multiple tables having the same name are accessible. This usually occurs when the database connection have access to multiple schemas containing identical table names.

Possible solutions:

1) Use a database connection credential that has access to only one database schema.

2) Specify a schema name to the DatabaseConnection or DatabaseDataSourceConnection constructor.

3) Enable the qualified table name support (see How-to documentation).