All channels have an associated message queue. When a message enters the messaging system, a slave program determines to which message queue the message is enqueued. The enqueued messages are stored in message files in the channel queue directories. By default, these directories are stored at the following location: msg-svr-base/data/queue/channel/*. Information on message queue sizing can be found at Disk Sizing for MTA Message Queues in Sun Java Communications Suite 5 Deployment Planning Guide
Do not add any files or directories in the MTA queue directory (that is, the value of IMTA_QUEUE in the imta_tailor file) as this will cause problems. When using a separate file system for the MTA queue directories, create a subdirectory under that mount point and specify that subdirectory as the value of IMTA_QUEUE.