在JasperReports中使用函数时,PHPJasperXML无法正常工作

I am using PHPJasperXML to create pdf reports in yii. http://www.simitgroup.com/?q=PHPJasperXML . I was able to create the pdf file successfully. But if I use any of the functions in the JasperReports then it is not working.

For example I have created group in the report and want to round the total in the group footer. Here is the code new $V{totalamount_1}.round(MathContext(4,RoundingMode.HALF_UP)). If i use this code then the page is showing blank in PHPJasperXML. In the preview of iReport designer it is showing correctly.