I don't want it in the WAR. However, if it is added in any way to the WEB-INF/lib directory of the WAR project, you will face the issue described in this thread (unless you are using JBoss AS 4.2.2).
With the way Seam is designed, if you have Seam on the classpath twice, the results are undefined. In some cases it will work, others it will not. The reason for the initial warning is that Seam bundles faces-config.xml and JSF is going to find it twice and try to start the phase listener twice. Hmm...
-Dan