Unable to locate Spring NamespaceHandler for XML schema namespace [http://www.springframework.org/schema/security]

You need a spring-security-config.jar on your classpath.

The exception means that the security: xml namescape cannot be handled by spring “parsers”. They are implementations of the NamespaceHandler interface, so you need a handler that knows how to process <security: tags. That’s the SecurityNamespaceHandler located in spring-security-config