Erro do VRaptor ao subir TOMCAT

GRAVE: Exception starting filter vraptor

java.lang.NoClassDefFoundError: org/apache/log4j/Level

at org.slf4j.LoggerFactory.getSingleton(LoggerFactory.java:223)

at org.slf4j.LoggerFactory.bind(LoggerFactory.java:120)

at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:111)

at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:269)

at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:242)

at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:255)

at br.com.caelum.vraptor.VRaptor.(VRaptor.java:60)

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:526)

at java.lang.Class.newInstance(Class.java:379)

at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:140)

at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:258)

at org.apache.catalina.core.ApplicationFilterConfig.(ApplicationFilterConfig.java:105)

at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4809)

at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5485)

at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)

at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)

at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)

at java.util.concurrent.FutureTask.run(FutureTask.java:262)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)

at java.lang.Thread.run(Thread.java:745)

Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Level

at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1718)

at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1569)

… 24 more

<context-param>
    <param-name>log4j-config-location</param-name>
    <param-value>WEB-INF/log4j.properties</param-value>
</context-param>

<filter>
<filter-name>vraptor</filter-name>
<filter-class>br.com.caelum.vraptor.VRaptor</filter-class>