From Dockwalk, here is an article about what can happen carrying weapons aboard.
http://www.dockwalk.com/Essentials/HotTopics.aspx?id=25058

And from one of my favorite blogs to follow, FeralJundi with a story from the commercial side of maritime security/piracy.
http://feraljundi.com/2009/06/04/maritime-security-inside-story-of-somali-pirate-attack/#more-806
