well, duh
have u played dekaron at all?
if you die you get returned to your return point, no matter what map u are on, the trick to make a prison is to make it where they cant move from that map, which means NO KILLING THEM as the first rule, may wanna make sure they cant go thru any npc's as well, or portal scrolls u can turn things liek that off in the maplist file, first line makes the file pretty self explanatory . . . .
and of course they can talk in chat, but only on that map, so just leave them there like the brits done to the aussies back in the day