| SAXONICA | 
The saxon:script element is a top-level element. 
            It is used to define an implementation
            for an extension function that will be used by Saxon. With
            other processors, a different implementation of the same function can be selected, 
            using mechanisms defined by that processor (for example, xalan:script).
         
The attributes for saxon:script are the same as the attributes
            of the xsl:script element defined in the (now withdrawn) XSLT 1.1
            working draft.
         
The language attribute is mandatory, and must take the value "java". 
            The values "javascript", "ecmascript", or a QName are also permitted, but in this
            case Saxon ignores the saxon:script element.
         
The implements-prefix attribute is mandatory, its value must be a namespace
            prefix that maps to the same namespace URI as the prefix used in the extension function
            call.
         
The src attribute is mandatory for language="java", its value must take the
            form "java:fully.qualified.class.Name", for example "java:java.util.Date". It defines
            the class containing the implementation of extension functions that use this prefix.
         
The archive attribute is optional, its value is a space-separated list of URLs
            of folders or JAR files that will be searched to find the named class. If the attribute
            is omitted, the class is sought on the classpath.