ERROR [WsdlTestCase] Failed to create test step for [DataSource]

Hi,

I'm trying to access my soapui project from the api and execute selected testcase.
the following line: wsdlProject = new WsdlProject([filename])
returns this message: ERROR [WsdlTestCase] Failed to create test step for [DataSource]

I noticed this error in soapUI pro console while running the same test from soapUI gui. after placing the jdbc jar under bin/ext the issue was solved.

how can I make it work the same through the api?

Thanks,
Chen.