The reason was this in faces-config.xml:
<application> <el-resolver>org.jboss.seam.jsf.SeamELResolver</el-resolver> </application>
<listener> <listener-class>com.sun.faces.config.ConfigureListener</listener-class> </listener>
Little information about the ConfigureListener here:
http://jira.icefaces.org/browse/ICE-1273
Seems to be the usual black magic.