Do not use classpath. This may cause problems with different ClassLoaders (container vs. application). WEB-INF is always the better choice.
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-config.xml</param-value>
</context-param>
and
<bean id="placeholderConfig" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="location">
<value>/WEB-INF/social.properties</value>
</property>
</bean>