Using timestamps causing trouble with WSDL generation

I have some TIMESTAMP columns in my Oracl开发者_如何学Goe database and the JPA entities use java.sql.Timestamp to map them. Using RAD 7, I was trying to generate Web Services for my EJB methods, but it fails with the error:

The class java.sql.Timestamp is defined in a java or javax package and cannot be converted into an xml schema type

What should be done to convert the timestamps to xml schema type? I would like to retain timestamps in the database. Do I need to change the datatypes and entities?

Please provide your suggestions.

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Perhaps not an answer to your question, but why do you need java.sql.Timestamp in JPA entities? JPA can map database timestamps to java.util.Date:

@Temporal(TemporalType.TIMESTAMP) 
private Date timestampField;