[Beta 9.5.6] Cow path-finding non-existen to Flint's Finger

[shiftsnake]

I like to point out that English is not my strong point, so please don't get offend by it. 

Hi, not sure if this has been reported before but I found a minor/non-important bug when I tried to deliver a cow herds to the marshal near Flint's Finger.

1) This picture show that I am leading a cow herds to Flint's Finger. http://i.imgur.com/l23bwvH.jpg?1

2) There seem to be a invisible wall and the herds walk along with it. http://i.imgur.com/EeOXm3L.jpg?1

3) I use teleport cheat at this point to see if I can force the herds in. http://i.imgur.com/htoU52M.jpg?1

4) I got the same result, the herd refuse to go near the castle. http://i.imgur.com/EE0MzxR.jpg?1

The entire area is block off for the cows, not just that particular spot.