I resolve my problem (i can display a login page): 1. you don't need myfaces-api and myfaces-impl with jboss 5 only tomahawk (see http://wiki.jboss.org/wiki/Wiki.jsp?page=JBoss5AndMyFaces for further details) I think it should be valuable to add some informations in seam documentation. 2. You don't need to use manifest dependency for using jar in the web app. 3. Be careful, it seems that JBoss 5 Beta 1 is not doing clean-undeploy (i've to remove some files in tmp/deploy and work) Sebastien View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4045292#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...