How do I configure Spring and SLF4J so that I can get logging?

I've got a maven & spring app that I want logging in. I'm keen to use SLF4J.

I want to put all my config files into a directory {classpath}/config including log4j.xml and then init using a spring bean.

e.g.

<bean id="log4jInitialization" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
    <property name="targetClass" value="org.springframework.util.Log4jConfigurer"/>
    <property name="targetMethod" value="initLogging"/>
    <property name="arguments">
        <list>
            <value>classpath:config/log4j.xml</value>
        </list>
    </property>
</bean>

However I get this warning and no logging.

log4j:WARN No appenders could be found for logger (org.springframework.context.support.ClassPathXmlApplicationContext). log4j:WARN Please initialize the log4j system properly. log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

I've googled around and can't find a simple example on setting this up. Any ideas?