Make sure, following jar file included in your class path and lib folder.
spring-core-3.0.5.RELEASE.jar
if you are using maven, make sure you have included dependency for spring-core-3xxxxx.jar file
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${org.springframework.version}</version>
</dependency>
Note : Replace ${org.springframework.version} with version number.