java.lang.ClassNotFoundException: XMLGregorianCalendarImpl

Say we have a web service using JAX-WS on Glassfish v2.1, and we have an operation using a XMLGregorianCalendar type. When this operation is called, an exception can be thrown:

java.lang.ClassNotFoundException: org.apache.xerces.jaxp.datatype.XMLGregorianCalendarImpl

In the {glassfish install map}/lib location we have a launcher.xml and a launcher.properties file. Inside the XML there is a reference

<sysproperty key="javax.xml.parsers.SAXParserFactory" value="com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl" />
assuming Xerces is already available inside the server shared libraries map. By installing Xerces the exception problem is solved.