Printemps Erreur de Sécurité: cvc-complexe-type.2.4.c: La mise en correspondance générique est stricte, mais aucune déclaration ne peut être trouvé pour l'élément 'http'

Je suis en train de travailler sur un Google App Engine et je suis en train d'intégrer le Printemps de Sécurité pour le projet, mais je reçois le ci-dessous dès que je lance l'application Google App Engine:

15-Jul-2013 13:09:13 com.google.apphosting.utils.jetty.JettyLogger warn
WARNING: Nested in
org.springframework.beans.factory.xml.XmlBeanDefinitionStoreException: Line 16 in   XML document from ServletContext resource [/WEB-INF/spring-security.xml] is invalid;     nested exception is org.xml.sax.SAXParseException: cvc-complex-type.2.4.c: The 
matching wildcard is strict, but no declaration can be found for element 'http'.:
org.xml.sax.SAXParseException: cvc-complex-type.2.4.c: The matching wildcard is strict, but no declaration can be found for element 'http'.
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:195)
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.error(ErrorHandlerWrapper.java:131)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:384)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:318)
at com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator$XSIErrorReporter.reportError(XMLSchemaValidator.java:423)
at com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator.reportSchemaError(XMLSchemaValidator.java:3188)
at com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator.handleStartElement(XMLSchemaValidator.java:1933)
at com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator.startElement(XMLSchemaValidator.java:711)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(XMLNSDocumentScannerImpl.java:400)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2756)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:647)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:140)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(DOMParser.java:232)
at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(DocumentBuilderImpl.java:284)
at org.springframework.beans.factory.xml.DefaultDocumentLoader.loadDocument(DefaultDocumentLoader.java:75)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:388)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:334)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:302)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:174)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:209)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:180)
at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:125)
at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:94)
at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:131)
at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:522)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:436)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:385)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:284)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111)
at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java:548)
at org.mortbay.jetty.servlet.Context.startContext(Context.java:136)
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.HandlerWrapper.doStart(HandlerWrapper.java:130)
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 com.google.appengine.tools.development.JettyContainerService.startContainer(JettyContainerService.java:249)
at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:307)
at com.google.appengine.tools.development.AutomaticServerInstanceHolder.startUp(AutomaticServerInstanceHolder.java:26)
at com.google.appengine.tools.development.AbstractServer.startup(AbstractServer.java:80)
at com.google.appengine.tools.development.Servers.startup(Servers.java:82)
at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:237)
at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:339)
at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:48)
at com.google.appengine.tools.development.DevAppServerMain.<init>(DevAppServerMain.java:274)
at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:250) 

C'est la façon dont ma spring-security.xml fichier ressemble à

<beans:beans xmlns="http://www.springframework.org/schema/security"
xmlns:beans="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context 
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/security
http://www.springframework.org/schema/security/spring-security.xsd">
<context:component-scan base-package="com.myapp.security" />
<beans:bean id="customAuthenticationProvider"
class="com.myapp.security.CustomAuthenticationProvider"></beans:bean>
<http auto-config="true">
<intercept-url pattern="/" access="IS_AUTHENTICATED_ANONYMOUSLY" />
<intercept-url pattern="/**" access="ROLE_USER" />
<form-login login-page="/login" default-target-url="/"
authentication-failure-url="/loginfailure" />
<logout logout-success-url="/logout" />
</http>
<authentication-manager>
<authentication-provider ref="customAuthenticationProvider" />
</authentication-manager>
</beans:beans>

J'ai ajouté spring-security-core-3.1.1.RELEASE.jar dans le classpath. Je ne suis pas en mesure de résoudre cette erreur. J'apprécierais vraiment l'aider.

Merci d'avance!