Generating BIRT PDF reports with a scheduler/cron job

Hello,
I need to automate the BIRT report generation via a cron job to generate PDFs.
I've been looking at 2 possibilities:
1) runReport batch file:
I can generate the sample report but when I want to generate a Jazz (RTC-based) report I get the error:

Mar 15, 2013 4:28:28 PM org.eclipse.birt.report.data.adapter.impl.ModelAdapter adaptDataSet
WARNING: handle type: org.eclipse.birt.report.model.api.OdaDataSetHandle
Mar 15, 2013 4:28:28 PM org.eclipse.birt.report.data.adapter.impl.ModelAdapter adaptDataSet
WARNING: handle type: org.eclipse.birt.report.model.api.OdaDataSetHandle
Mar 15, 2013 4:28:28 PM org.eclipse.birt.report.data.adapter.impl.ModelAdapter adaptDataSet
WARNING: handle type: org.eclipse.birt.report.model.api.OdaDataSetHandle
Mar 15, 2013 4:28:28 PM org.eclipse.birt.data.engine.odaconsumer.Driver doGetDriverManifest
SEVERE: Cannot find or process the ODA data source extension configuration.java.lang.IllegalArgumentException: Cannot find the ODA dataSource extension (com.ibm.team.reports.generic.dataSource).
 Check the workspace log file for any problems with loading the extension bundleand its dependencies.
        at org.eclipse.datatools.connectivity.oda.util.manifest.ManifestExplorer.getExtensionManifest(ManifestExplorer.java:200)
        at org.eclipse.birt.data.engine.odaconsumer.Driver.doGetDriverManifest(Driver.java:147)
        at org.eclipse.birt.data.engine.odaconsumer.Driver.findDataSourceExtensionConfig(Driver.java:123)
        at org.eclipse.birt.data.engine.odaconsumer.Driver.getDriverExtensionConfig(Driver.java:78)
        at org.eclipse.birt.data.engine.odaconsumer.Driver.getExtensionConfig(Driver.java:60)
        at org.eclipse.birt.data.engine.odaconsumer.Driver.getDriverHelper(Driver.java:93)
        at org.eclipse.birt.data.engine.odaconsumer.DriverManager.getDriverHelper(DriverManager.java:98)
        at org.eclipse.birt.data.engine.odaconsumer.ConnectionManager.openConnection(ConnectionManager.java:151)
        at org.eclipse.birt.data.engine.executor.DataSource.newConnection(DataSource.java:190)
        at org.eclipse.birt.data.engine.executor.DataSource.open(DataSource.java:178))

What am i doing wrong? I check the ODA jar is part of the BIRT runtime plugins directory...

2) Use the IReportViewerService from RTC:
I call com.ibm.team.reports.service.internal.IReportViewerService with the parameters:
__format=pdf
.__projectAreaUUID=xxx
__ownerUUID=xxx

However how to a create a script to specify the output file name and to handle the authentication?

Has anyone done that? Is it possible?
Any pointers would be greatly appreciated.

Thanks in advance