I have this bug too.
The following links are from a thread about the Ken and Gabby banter bug, which was fixed with patch 4. I'm sharing the links because Dusty Everman was active in the thread and explained what it takes to fix bugs and why some bugs may not be fixed.
Ken and Gabby?
http://social.bioware.com/forum/1/topic/325/index/10147092/2#10224650
http://social.bioware.com/forum/1/topic/325/index/10147092/3#10569444
http://social.bioware.com/forum/1/topic/325/index/10147092/4#10663496
I've read somewhere on BSN that the Leviathan/EC bug may not occur if you start a new game, but I haven't tried this myself. When I first noticed it I tried "Repair Install", but it didn't help; I've been tempted to try a few other things, but haven't had the time to experiment with anything yet.
