monster spawner does not react to spawnmonster false in server

monster spawner in dungeon is still spawning monsters even if monster spawning is disabled in server properties

What I expected to happen was...:
NO MONSTERS

What actually happened was...:
monsters spawnng in dungeons

Steps to Reproduce:
1. set server with spawn monsters false in properties
2. run server
3. login to server in a game and locate dungeon