From: Felipe Gaúcho <fgaucho_at_gmail.com>
Date: Wed, 27 Aug 2008 13:16:26 +0200

you can generate Enum that I believe is enough for your purposes. Use
SimlpeTypes with enumeration attribute for that........

Example:

<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
        xmlns:xjc="http://java.sun.com/xml/ns/jaxb/xjc"
        xmlns:xsd="http://www.w3.org/2001/XMLSchema"
        jaxb:extensionBindingPrefixes="xjc" jaxb:version="2.0">

        <xsd:simpleType name="publisher.i18n">
                <xsd:restriction base='xsd:string'>
                        <xsd:enumeration value="publisher.ok" />
                        <xsd:enumeration value="publisher.not.ok" />
                </xsd:restriction>
        </xsd:simpleType>
.....