struts-config.xml

 <message-resources
  parameter="jp.co.jip.resources.ApplicationResources" />
 <message-resources
  parameter="jp.co.jip.resources.ApplicationResources_img"
  key="img" />
 <message-resources
  parameter="jp.co.jip.resources.ApplicationResources_url"
  key="url" />
 <message-resources
  parameter="jp.co.jip.resources.ApplicationResources_popup"
  key="popup" />
 <message-resources
  parameter="jp.co.jip.resources.ApplicationResources_version"
  key="version" />

JSP中 

<bean:message key="button.torikeshi_sakusei" />