URGENT...cant load my own jasper reports to Open reports

hi
i need to use Open reports  to retrieve data from postgresql DB and generate online PDFs.
but wen i asdd my jasper reports to it , i get errors like 
"Error creating report: Error loading object from file : d:\tomcat\tomcat\webapps\openreports\reports\ShapesReport.jasper" at athe front- end 
and 

"java.io.InvalidClassException: dori.jasper.engine.base.JRBaseReport; local class
 incompatible: stream classdesc serialVersionUID = 500, local class serialVersio
nUID = 406" at the tomcat server

plz help .............

annu