The JBossAS deploy/mail-service.xml configures a JavaMail session binding into JNDI. The default service configuration will need altering for your network. http://wiki.jboss.org/wiki/Wiki.jsp?page=JavaMail describes the service in more detail.

<components xmlns="http://jboss.com/products/seam/components"
        xmlns:core="http://jboss.com/products/seam/core"
        xmlns:mail="http://jboss.com/products/seam/mail">
        
    <mail:mail-session session-jndi-name="java:/Mail"/>
    
</components>

Here we tell Seam to get the mail session bound to java:/Mail from JNDI.