Erro com MyFaces

Assuntos Gerais Agile
#1

Pessoal, estou dando uma estudada em JSF com MyFaces e está dando o seguinte erro ao abrir a página.

javax.servlet.ServletException: Bean: sample.TabbedPaneSample, property: valorPrimeiroLabel
	javax.faces.webapp.FacesServlet.service(FacesServlet.java:152)
	org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:144)

A classe no arquivo faces-config.xml está definida assim:

<managed-bean>
  <managed-bean-name>tabbedPaneSample</managed-bean-name>
  <managed-bean-class>sample.TabbedPaneSample</managed-bean-class>
  <managed-bean-scope>request</managed-bean-scope>
  <managed-property>
   <property-name>valorInputTab1</property-name>
   <property-class>java.lang.String</property-class>
   <value/>
  </managed-property>
  <managed-property>
   <property-name>valorInputTab2</property-name>
   <property-class>java.lang.String</property-class>
   <value/>
  </managed-property>
  <managed-property>
   <property-name>valorPrimeiroLabel</property-name>
   <property-class>java.lang.String</property-class>
   <value/>
  </managed-property>
  <managed-property>
   <property-name>valorSegundoLabel</property-name>
   <property-class>java.lang.String</property-class>
   <value/>
  </managed-property>
 </managed-bean>

O que pode estar errado ?

#2

Faltou a configuração do extensionsFilter no teu web.xml

http://myfaces.apache.org/tomahawk/extensionsFilter.html

#3