var serverName = controller.getServerName();
var reportName = 'classic_tom_test3_params.jrxml';//but really filled
in by user from a FID - get same result if ends in .jasper - ie no
compile
var varOutput =  globals.PITC_jasper_export_file;//filled from a FID
where user sets the filename from a selector dialog so in smart client
it is on the client machine
var outputFormat = globals.PITC_jasper_export_type;//default = 'view'
but set up by user to 'pdf' etc
var locale = null;

try {
var result = plugins.jasperPluginRMI.jasperReport(serverName,
reportName, varOutput, outputFormat, reportParameters, locale );
    } catch (e) {
    msg = "PITC_printJasperReport: DEBUG: Exception from plugin: "
    if (e == undefined) {
        msg += "exception 'e' is undefined";
    }
    else if (e.message == undefined){
        msg += "exception message is undefined";
    }
    else {
        msg += "message: <" + e.message + ">";
    }

I am expecting a byte array to be returned when output is to a file
but instead I get an exception sometimes where the exception is
undefined. Other times I get nothing in logs and NO file created.