freezing monsters bug/exploit

[Celestia]

Versions
Windows 7, Manaplus 1.5.1.3

Bug Description
It is possible to freeze almost any monster that is close to a door. The frozen monster will stand still and not fight back when attacked.

Steps to Reproduce
1. Get a monster to follow you to a door between maps.
2. Go in and out of the door to switch maps numerous times and keep it up until the monster stops moving. Sometimes this happens during the first try other times it takes numerous cycles to cause the monster to freeze up.
3. Attack the monster and it will not fight back.

Note this worked anywhere that I tried in the game. The easiest place to reproduce the bug is on maps/046-3.tmx by the door around player position (83, 40) with a Yeti.

Actual Behavior/Expected Behavior
Upon entering the new map after swapping maps quickly enough times the monsters will freeze and allow the player to attack them in complete safety.

Troubleshooting/Testing Steps Attempted
I tested this bug/exploit in other maps and was able to also reproduce it. So I believe this is a global bug that is not connected with any individual map.

[o11c]

Yes, this is known. I have only *verified* that it happens if the both sides of the warp are on the same map.

Since mob AI code is officially "scary", the best solution is just a workaround: put every contiguous area of a map on its own map. But I also have ideas about manual preprocessing of the pathfinding code ...