cannot assign instance of net.sf.jasperreports.engine.base.JRBaseStaticText to f

在tomcat5.5下面可以正常运行，放到weblogic下就出现如下问题
java.lang.ClassCastException: cannot assign instance of net.sf.jasperreports.engine.base.JRBaseStaticText to field net.sf.jasperreports.engine.base.JRBaseLineBox.boxContainer of type net.sf.jasperreports.engine.JRBoxContainer in instance of net.sf.jasperreports.engine.base.JRBaseLineBox
.....
at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:88)
at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:515)
at net.sf.jasperreports.engine.JasperRunManager.runReportToPdf(JasperRunManager.java:385)
报错的地方：byte[] bytes = JasperRunManager.runReportToPdf(reportFile.getPath(),
parameters, ds);
跟踪的时候在红色那一行已经报错，参数没有问题。
很郁闷，无法找到原因。。哪位兄弟遇到过类似问题，帮下忙，能给点提示也好。

------解决方法--------------------------------------------------------
你的jrxml可能有问题


java.lang.ClassCastException: cannot assign instance of net.sf.jasperreports.engine.base.JRBaseStaticText to field

你的jrxml可以在ireport编译成功吗?