On my test project, this error has finally been resolved.
You don't have to specify Database Schema Name and Database Catalog Name but only one one these parameters. With the catalog, you can browse the database when you Seam Generate Entities to choose the tables to work with in your application.
I don't remember if it's the only action required to fix it.
I now have on my real project, generated with the same method, another error :
13 oct. 2010 17:29:51 com.sun.facelets.FaceletViewHandler handleRenderException
GRAVE: Error Rendering View[/TEPersonnePrsList.xhtml]
javax.faces.FacesException: javax.el.PropertyNotFoundException: /TEPersonnePrsList.xhtml @19,93 value="#{tEPersonnePrsList.tEPersonnePrs.prsNom}": Property 'tEPersonnePrs' not found on type org.domain.stamas.session.TEPersonnePrsList_$$_javassist_seam_2
at javax.faces.component.UIOutput.getValue(UIOutput.java:187)
...
Caused by: javax.el.PropertyNotFoundException: /TEPersonnePrsList.xhtml @19,93 value="#{tEPersonnePrsList.tEPersonnePrs.prsNom}": Property 'tEPersonnePrs' not found on type org.domain.stamas.session.TEPersonnePrsList_$$_javassist_seam_2
at com.sun.facelets.el.TagValueExpression.getValue(TagValueExpression.java:73)
My table is called t_e_peronne_prs and I havn't made any change in the java or xhtml files generated by Seam Generate Entities.
I've serached on the Internet but didn't found anything for me.