ClassNotFoundException Error when starting tomcat

I'm trying to setup the tomcat server from eclipse, but this error has beaten me for a long and i didn't find any solution..

I tried:

adding spring-context, spring-core, spring-web dependencies to the classpath.
modifying the project properties(Deployment Assembly section).
cleaning the tomcat server directory.

this is my web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">

    <!-- The definition of the Root Spring Container shared by all Servlets and Filters -->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/spring/root-context.xml</param-value>
    </context-param>

    <!-- Creates the Spring Container shared by all Servlets and Filters -->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <!-- Processes application requests -->
    <servlet>
        <servlet-name>appServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>appServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

</web-app>

and this is the tracktrace:

Nov 03, 2014 5:40:26 PM com.springsource.tcserver.security.PropertyDecoder <init>
INFO: tc Runtime property decoder using memory-based key
Nov 03, 2014 5:40:27 PM com.springsource.tcserver.security.PropertyDecoder <init>
INFO: tcServer Runtime property decoder has been initialized in 153 ms
Nov 03, 2014 5:40:27 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["http-bio-8080"]
Nov 03, 2014 5:40:28 PM com.springsource.tcserver.serviceability.rmi.JmxSocketListener init
INFO: Started up JMX registry on 127.0.0.1:6969 in 189 ms
Nov 03, 2014 5:40:28 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 1258 ms
Nov 03, 2014 5:40:28 PM org.apache.catalina.core.StandardService startInternal
INFO: Starting service Catalina
Nov 03, 2014 5:40:28 PM org.apache.catalina.core.StandardEngine startInternal
INFO: Starting Servlet Engine: VMware vFabric tc Runtime 2.8.2.RELEASE/7.0.35.B.RELEASE
Nov 03, 2014 5:40:28 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor /home/karim/Downloads/.springsource/vfabric-tc-server-developer-2.8.2.RELEASE/base-instance/conf/Catalina/localhost/task-manager.xml
Nov 03, 2014 5:40:28 PM org.apache.catalina.startup.SetContextPropertiesRule begin
WARNING: [SetContextPropertiesRule]{Context} Setting property 'source' to 'org.eclipse.jst.jee.server:task-manager' did not find a matching property.
Nov 03, 2014 5:40:28 PM org.apache.catalina.core.StandardContext listenerStart
SEVERE: Error configuring application listener of class org.springframework.web.context.ContextLoaderListener
java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderListener
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
    at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:527)
    at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:509)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:137)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4733)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5291)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:657)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1637)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
    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)

Please, if you need another thing just let me know.

The class in question is in spring-web-?????RELEASE.jar. Go to your war and either open it with the likes of winzip or 7Zip and look for the jar in WEB-INF/lib, my guess is that it isn't there. If your using maven include the dependency as:

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>${or.springframework-version}</version>
</dependency>

If you're not using maven and I imagine you're doing this in Eclipse as you mentioned deployment assembly, you must add whatever libraries you used to make these jars available to your compile to the eclipse build. Or you can simply move the jar to WEB-INF/lib.

Check your war after the build for the jar file.