Some time ago, Feaelin made a change to allow players to move across region borders without respect for cost. This change was intended to help players meet up for RP more easily, although we still ask everyone to consider distance and travel times realistically within their RPs. The change seems to have disappeared at some point, however, and so I've just put it back again, and this time I've set a glyph of protection on the code. (... is that a real thing? Gosh, aren't I mysterious!)
If you still have trouble crossing borders, please file a bug using the normal 'bug' command.
Thanks!