Error while Exporting DocumentType from TN


I am new to RosettaNet…We are going to upgrade 4.x to 6.5, When I am trying to export PIP related document types from 4.x TradingNetworks console it showing error like…as under…

Error occured while retrieving document type

The class for the document type is not found in the classpath. Please make sure that the classpath is set up properly.

Pls give solution for the above problem