JAVA Error

Version 1
    This document was generated from CDN thread

    Created by: Sarah Barnes on 09-05-2013 08:06:24 AM
    Can anyone help - a customer has tried to run a customised report today and has come up with the following error on attached document. it was working fine last week and all the other customised reports are working ok, Just checking to see if anyone has seen this before and if so - what was the solution - other than reimporting the report!    
    Thanks Sarah