This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
This is most probably an error if the attribute is of type xs:dateTime. And it is probably the cause of validating unmarshalling. It should either end with Z rather than N or some standard conformant syntax. But, however probably, the issue cannot be resolved without seeing the schema or actually data binding xml-to-javatype-adapter if any.