Most often, the Action Mappings will be automatically reloaded if the WAR is redeployed. If not, there are two things you can try: Setting the reload property to true and destroying the configuration.

Setting Reload to True

### Configuration reloading
### This will cause the configuration to reload xwork.xml when it is changed
struts.configuration.xml.reload=true

Destroying the Configuration

Create a utility Action that calls destroyConfiguration.

// ...
String execute() {
  com.opensymphony.xwork.config.ConfigurationManager.destroyConfiguration();
  return SUCCESS;
}

Invoking destryConfiguration should destroy the current configuration and force the configuration to be reloaded on next request (which you might want to make yourself!).