Idle Telnet Timeouts

[ArcticFox]

Not sure if this is the right list to ask this on, too many to choose 
from and none of the others looked like what I wanted. Anyway; here's 
the deal, I'm running a TinyMUSH world on my system. The problem that 
I'm having is that when a player is idle for any length of time they 
get disconnected with a "Network error: POSIX error: Operation timed 
out" as far as I can tell, this shouldn't be happening. Neither my ISP 
nor the MUSH software is disconnecting them. In fact the MUSH has an 
idle timeout in it to d/c players that have been idle for too long, 
this isn't activating however.

Anyone have any ideas on how I can stop this?