Error with logback

I am getting this error. I tried to dig deeper, but couldn't find what
is going on. This is the contents of my applicationContext.xml in the
web-app :

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:configurator="http://cocoon.apache.org/schema/configurator"
	xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
                           http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util-2.5.xsd

http://cocoon.apache.org/schema/configurator
http://cocoon.apache.org/schema/configurator/cocoon-configurator-1.0.1.xsd">
	<configurator:settings runningMode="dev" />
	<bean name="org.apache.cocoon.spring.configurator.logback"
class="org.apache.cocoon.spring.configurator.logback.LogbackConfigurator"
scope="singleton">
		<property name="resource" value="/WEB-INF/logback.xml" />
	</bean>
</beans>

This is the error message:


2013-03-20 21:10:59.499::WARN:  Nested in
org.springframework.beans.factory.BeanCreationException: Error
creating bean with name
'org.apache.cocoon.spring.configurator.logback' defined in
ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation
of init method failed; nested exception is
java.lang.NullPointerException:
java.lang.NullPointerException
	at org.apache.cocoon.spring.configurator.logback.LogbackConfigurator.afterPropertiesSet(LogbackConfigurator.java:63)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1514)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1452)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
	at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:605)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:925)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:472)
	at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:383)
	at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:283)
	at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111)
	at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java:540)
	at org.mortbay.jetty.servlet.Context.startContext(Context.java:135)
	at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
	at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:510)
	at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
	at org.mortbay.jetty.plugin.Jetty6PluginWebAppContext.doStart(Jetty6PluginWebAppContext.java:110)
	at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:40)
	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:40)
	at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152)