export jsp to excel application is not working

[Nitin Surnar]

Hi Friends,

I have developed an application in struts 1 to export the table on jsp to excel and save it 

with reference to http://www.vaannila.com/struts/struts-example/struts-export-work-book-to-excel-example-1.html

Its working fine on my local system but its not working on google app engine 

it shows error page as 

Error: Server Error

The server encountered an error and could not complete your request.

If the problem persists, please report your problem and mention this error message and the query that caused it.

Kindly tell me any suggestion on configuration to be done

Thanks,

Nitin