SpringObjectFactory Error in creating application in Struts 2.3.7

Recently I tried to work with Struts 2 (2.3.7) Version and it gives the impression that all the Jars available in lib directory of the distribution are required to run. But seems that is not the case because it causes the following exception in Spring.

org.apache.catalina.core.StandardContext filterStart
SEVERE: Exception starting filter struts2
Class: com.opensymphony.xwork2.spring.SpringObjectFactory
File: SpringObjectFactory.java
Method: getClassInstance
Line: 230 - com/opensymphony/xwork2/spring/SpringObjectFactory.java:230:-1
    at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:483)
    at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:74)
    at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:51)
    at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:295)
    at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:422)
    at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:115)
    at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4072)
    at org.apache.catalina.core.StandardContext.start(StandardContext.java:4726)
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
    at org.apache.catalina.core.StandardHost.start(StandardHost.java:840)
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
    :754)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

Caused by: java.lang.NullPointerException
    at com.opensymphony.xwork2.spring.SpringObjectFactory.getClassInstance(SpringObjectFactory.java:230)
    at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:429)
    at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:471)
    ... 20 more

This Exception puzzles many people because it is related to Spring. To solve this you should just use the below mentioned Jars in the WEB-INF/lib directory only,

asm-3.3.jar
asm-commons-3.3.jar
asm-tree-3.3.jar
commons-fileupload-1.2.2.jar
commons-io-2.0.1.jar
commons-lang3-3.1.jar
freemarker-2.3.19.jar
javaassist-3.11.0.GA.jar
ognl-3.0.5.jar
struts2-core-2.3.7.jar
xwork-core-2.3.7.jar