NoClassDefFoundError: Could not initialize class freemarker.template.Configuration when configuring custom spring modules in JBoss EAP 6

Issue

Hello, I've setup some modules for Spring. I have an application with a jboss-deployment-structure.xml in an application that has dependencies on spring and freemarker modules, however I'm getting this exception below:

WARN  [org.springframework.beans.factory.support.DefaultListableBeanFactory] (MSC service thread 1-2) FactoryBean threw exception from getObjectType, despite the contract saying that it should return null if the type of its object cannot be determined yet: java.lang.NoClassDefFoundError: Could not initialize class freemarker.template.Configuration
  at java.lang.Class.forName0(Native Method) [rt.jar:1.6.0_30]
  at java.lang.Class.forName(Class.java:169) [rt.jar:1.6.0_30]
  at org.springframework.ui.freemarker.FreeMarkerConfigurationFactoryBean.class$(FreeMarkerConfigurationFactoryBean.java:69) [spring.jar:2.5.6]
  at org.springframework.ui.freemarker.FreeMarkerConfigurationFactoryBean.getObjectType(FreeMarkerConfigurationFactoryBean.java:69) [spring.jar:2.5.6]
  at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getTypeForFactoryBean(FactoryBeanRegistrySupport.java:55) [spring.jar:2.5.6]
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getTypeForFactoryBean(AbstractAutowireCapableBeanFactory.java:620) [spring.jar:2.5.6]
  at org.springframework.beans.factory.support.AbstractBeanFactory.isTypeMatch(AbstractBeanFactory.java:450) [spring.jar:2.5.6]
...

My Spring module looks like this:

<module xmlns="urn:jboss:module:1.1" name="spring" slot="2.5.6">
    <resources>
        <resource-root path="aspectjrt.jar"/>
        <resource-root path="aspectjweaver.jar"/>
        <resource-root path="jaxws-spring-1.8.jar"/>
        <resource-root path="spring.jar"/>
        <resource-root path="xbean-spring-2.7.jar"/>
        <resource-root path="spring-webmvc-2.5.6.jar"/>
    </resources>

    <dependencies>
        <module name="javax.api" export="true"/>
        <module name="javaee.api" export="true"/>
        <module name="org.apache.commons.logging"/>
    </dependencies>
</module>