Mdaemon email server software - kind of urgent

[CourtesyFlush]

If anyone out there uses this software on their email server...do you know how to increase the amount of connections to a specific email box at one time? Like, do you know how to configure it so that when a mailbox is being accessed, it does not lock it and allows another concurrent connection to be opened with the same mailbox? I need this information to help out a client tomorrow morning, and I can't seem to find this information anywhere online.
Help!

Thanks,

CF