In the enhanced client, I seem to always run into "invisible walls" when having spent extended periods of time in caves. It doesn't happen anywhere else. This could be related? Though the issue I mentioned has happened ever since the EC has been out.
BTW Supreem, on 5/7 of my characters, I got your 12th anniversary card. I appreciate it, but... really man. Sorry. I don't think it'll work out.