When SIMS connects to another messaging system, the channel might be unavailable and cause queuing the incoming messages. For this reason, the administrator needs to allocate sufficient storage in the directory /var/opt/SUNWmail, where all message queues and temporary files are stored.For example, the administrator needs to allocate 200 megabytes storage to store two days worth of messages for a mail system that transports 100 messages per day (i.e., each message is 1 megabyte).