INT 15 - TopView - SEND MESSAGE - "SETNAME" - ASSIGN NAME TO MAILBOX
        AH = 12h
        BH = 11h
        BL = mailbox to name
            00h DWORD on top of stack is mailbox handle
            02h use given task's mailbox (task's handle on top of stack)
            03h use current task's default mailbox
        STACK: DWORD length of name
               DWORD address of name
SeeAlso: AX=DE0Eh