Servoy JasperReports Plugin

Hi,
I´m trying to get the bytes Array from JasperReport to attach later in an email.
I use the following call to call jasperreport:
var rawData = plugins.jasperPluginRMI.runReport(server_name,reportName,null,'pdf',params);
In Webclient works fine. There´s not problem.
But in Smart Client throw me the following error:
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
java.lang.ClassNotFoundException: Class not whitelisted for RMI: net.sf.jasperreports.engine.JasperPrint......
How can I fix this problem?
Regards Javier Arroyo