Hold or delete message files from the PMDF queue area that
    contain specified substrings in their envelope From: address,
    Subject: header, or message content.

    Syntax

      CLEAN  [channel]

    Command Qualifiers             Defaults

    /CONTENT=substring             None
    /DATABASE                      See text
    /DELETE                        /HOLD
    /DIRECTORY_TREE                See text
    /ENV_FROM=substring            None
    /HOLD                          /HOLD
    /MATCH=keyword                 /MATCH=AND
    /MIN_LENGTH=n                  /MIN_LENGTH=24
    /SUBJECT=substring             None
    /THREADS=n                     /NOTHREADS
    /VERBOSE                       /NOVERBOSE