Cannot resolve reference to bean 'flowExecutor' while setting bean property 'flowExecutor'

I have a dispatcher-servlet.xml as below. In it I have mentioned flowRegistry attribute in flowExecutor. In other examples, flowregistry is given using the attribute ref. In this xsd, i dont find any ref attribute to refer to the flowregistry from flowExecutor. It is giving me the following error. I would be thankful if someone could help me to come out of this issue.

Cannot resolve reference to bean 'flowExecutor' while setting bean property 'flowExecutor'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'flowExecutor': Invocation of init method failed; nested exception is java.lang.NoSuchMethodError: org.springframework.webflow.execution.repository.support.AbstractFlowExecutionRepository.<init>(Lorg/springframework/webflow/conversation/ConversationManager;)V

dispatcher-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>  
<beans xmlns="http://www.springframework.org/schema/beans"  
  xmlns:context="http://www.springframework.org/schema/context"  
  xmlns:flow="http://www.springframework.org/schema/webflow-config"  
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
  xsi:schemaLocation="http://www.springframework.org/schema/beans  
    http://www.springframework.org/schema/beans/spring-beans-2.5.xsd  
    http://www.springframework.org/schema/context  
    http://www.springframework.org/schema/context/spring-context-2.5.xsd  
    http://www.springframework.org/schema/webflow-config  
    http://www.springframework.org/schema/webflow-config/spring-webflow-config-2.0.xsd">

<flow:flow-registry id="flowRegistry">
		<flow:flow-location path="/WEB-INF/hello-flow.xml"/>
	</flow:flow-registry>	
</beans>