An error occurred. Please contact the administrator of the application.java.lang.Exception: java.lang.NoClassDefFoundError: org/apache/log4j/Level
	at org.ametys.runtime.servlet.RuntimeServlet.init(RuntimeServlet.java:192)
	at org.mortbay.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:440)
	at org.mortbay.jetty.servlet.ServletHolder.doStart(ServletHolder.java:263)
	at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
	at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:685)
	at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
	at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1250)
	at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:517)
	at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:467)
	at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
	at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152)
	at org.mortbay.jetty.handler.ContextHandlerCollection.doStart(ContextHandlerCollection.java:156)
	at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
	at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152)
	at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
	at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
	at org.mortbay.jetty.Server.doStart(Server.java:224)
	at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
	at org.mortbay.xml.XmlConfiguration.main(XmlConfiguration.java:985)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.mortbay.start.Main.invokeMain(Main.java:194)
	at org.mortbay.start.Main.start(Main.java:534)
	at org.mortbay.start.Main.start(Main.java:441)
	at org.mortbay.start.Main.main(Main.java:119)
Caused by: java.lang.NoClassDefFoundError: org/apache/log4j/Level
	at org.slf4j.LoggerFactory.bind(LoggerFactory.java:128)
	at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:107)
	at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:295)
	at org.ametys.runtime.util.SLF4JLoggerManager.<init>(SLF4JLoggerManager.java:47)
	at org.ametys.runtime.util.SLF4JLoggerManager.<init>(SLF4JLoggerManager.java:35)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
	at java.lang.reflect.Constructor.newInstance(Unknown Source)
	at java.lang.Class.newInstance0(Unknown Source)
	at java.lang.Class.newInstance(Unknown Source)
	at org.apache.cocoon.servlet.CocoonServlet.newLoggerManager(CocoonServlet.java:898)
	at org.apache.cocoon.servlet.CocoonServlet.initLogger(CocoonServlet.java:821)
	at org.ametys.runtime.servlet.RuntimeServlet.initLogger(RuntimeServlet.java:273)
	at org.apache.cocoon.servlet.CocoonServlet.init(CocoonServlet.java:356)
	at org.ametys.runtime.servlet.RuntimeServlet.init(RuntimeServlet.java:170)
	... 26 more
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Level
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(Unknown Source)
	at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:392)
	at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:363)
	... 42 more