I am trying to break out the part of my context.xml that refers to the datasource so I can use different databases for testing and production. When I run within tomcat, everything works fine, but when I run my unit tests, I get a "error creating bean" exception due to "can't find bean 'dataSource'

Here are some specifics:
web.xml contains
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/spring-config.xml
/WEB-INF/spring-tiles-config.xml
/WEB-INF/spring-datasource.xml
</param-value>
</context-param>

versus my programmatic instantiation is:
String[] paths = {"/WEB-INF/spring-config.xml", "/WEB-INF/spring-datasource-test.xml"};
ctx = new ClassPathXmlApplicationContext(paths);

If I call ctx.getBeanDefinitionNames right after this initialization, it DOES include 'dataSource', yet the bean in spring-config.xml can't find it. Any thoughts?

-James