Sasi,
Is drools-spring in your classpath?
<groupId>org.drools</groupId>
<artifactId>drools-spring</artifactId>
<version>5.2.1.Final</version>
(The version may differ depending on which version of jBPM 5 you're using: see the pom.xml of your jbpm 5 jar and use the drools.version property value that's in that pom).
Regards,
Marco