ZK - Open Source Ajax Java Framework

Hello Sir/Madam,
I am creating report which will display details according to passed ID.I have added iReport-4.1.3-plugin in my netbean IDE 6.7.1.Using this,i have created one jrxml which is working fine when i am running it in ireport.I have added jasper 1.2.2 & ZK 0.7.4 plugin in netbean But when i am trying to run project & display it on browser with following code :

<window id="wndSelectReportType" width="250px" height="80px" title="Select Report Type" visible="false">
<caption> <toolbarbutton label="Close" onClick="wndSelectReportType.setVisible(false);"></toolbarbutton> </caption>
Please select type of report :
<combobox id="fileType" readonly="true" width="15%">
<comboitem id="RTF" label="rtf"></comboitem>
<comboitem id="PDF" label="pdf"></comboitem>
</combobox>
<div align="center">
<button id="generateReport" label="Generate Report"></button>
</div>
<jasperreport id="report" height="360px" ></jasperreport>
<zscript><![CDATA[
generateReport.onClick={

if(fileType.value==""){
Messagebox.show("Please select Report Type first...", "MyTask", Messagebox.OK, Messagebox.ERROR);
fileType.setFocus(true);
return;
}else{
Map parameters = new HashMap();
parameters.put("appID",session.getAttribute("selected_appointment"));

report.setSrc("report/report1.jasper");
report.setParameters(parameters);
report.setDatasource(new net.sf.jasperreports.engine.JREmptyDataSource());
report.setType(fileType.value);
}
}
]]></zscript>
</window>

It is giving an exception as :

SEVERE: Failed to load media, /view/g7hb/zk_comp_363/0/report/report1.rtf
>>java.lang.NullPointerException
>> at net.sf.jasperreports.engine.JRPropertiesMap.readObject(JRPropertiesMap.java:185)
>> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>> at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
>> at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
>> at java.lang.reflect.Method.invoke(Method.java:597)
>> at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:974)
>> at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1848)
>> at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1752)
>> at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328)
>> at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1946)
>> at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1870)
>> at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1752)
>> at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328)
>> at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1666)
>> at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1322)
>> at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1946)
>> at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1870)
>> at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1752)
>> at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328)
>> at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1946)
>> at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1870)
>> at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1752)
>> at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328)
>> at java.io.ObjectInputStream.readObject(ObjectInputStream.java:350)
>> at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:192)
>> at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:580)
>> at org.zkoss.zkex.zul.Jasperreport.doReport(Jasperreport.java:361)
>> at org.zkoss.zkex.zul.Jasperreport.access$100(Jasperreport.java:76)
>> at org.zkoss.zkex.zul.Jasperreport$ExtraCtrl.getMedia(Jasperreport.java:310)
>>...

where my report1.jasper file is in web-app/report/report1.jasper .

I am using example which is on : http://www.zkoss.org/zkdemo/reporting/jasperreport for help but it is generating above exception. Can you please tell me what's the problem ?

Thanking you in advance.