With PMDF DB you can create and maintain your own mailing lists.
    A mailing list is merely a collection of e-mail addresses with
    which you associate an alias. Or, looked at a little differently,
    a mailing list is an alias which expands to a list of e-mail
    addresses. When you address a mail message to the alias, it
    actually goes to all of the addressees listed in the mailing
    list. The act of sending a mail message to a mailing list is
    referred to as "posting".

    A mailing list is created in three steps:

    1. Create a text file containing the list of e-mail addresses
       associated with the mailing list. Each address should be on a
       separate line in the file. The file itself is referred to as a
       "mailing list file"; the addresses in the file are the mailing
       list's membership.

    2. Set the protection of the mailing list file so that it is
       world readable

       $ SET PROTECTION=(W:R) filename

       Here, FILENAME is the name of the mailing list file created in
       Step 1.

    3. Choose an alias name, ALIAS-NAME , to associate with the
       mailing list. Then, in PMDF DB, issue the commands

       db> add alias-name "<filename"
       db> set alias-name public

       FILENAME should include a full path specification including
       the disk and directory name.

    After these steps have been taken, the mailing list is set up and
    ready to use.

    For example, suppose the user sue@example.com wants to set up a
    mailing list named sample-list. The members of the mailing list
    will be bob@example.com, judy@example.com, ralph@sample.com,
    and sue@example.com. Sue first creates the mailing list file
    D1:[SUE]SAMPLE.DIS which contains the four lines

    bob@example.com
    judy@example.com
    ralph@sample.com
    sue@example.com

    She then makes sure the distribution file is world readable by
    explicitly setting its protection with the DCL SET PROTECTION
    command,

    $ SET PROTECTION=(W:R) D1:[SUE]SAMPLE.DIS

    Finally, Sue establishes the public alias FOO-LIST as follows:

    $ PMDF DB
    db> add foo-list "<d1:[sue]sample.dis"
    db> set foo-list public
    db> show foo-list attributes
    Key          Value
    -----------  -----------------------------
    foo-list     <d1:[sue]sample.dis
    Attributes:  public,no-expand,block-receipts,mail-address
    [1 entries shown]
    db>

    By declaring the list to be public, Sue is allowing other
    people to post messages to this mailing list. They should do
    so by addressing their messages to sue+sample-list@example.com.
    Messages so addressed will then be received by the members of the
    list as specified by the contents of the file D1:[SUE]SAMPLE.DIS.

    At any time you can add or remove members from the mailing list.
    You do so by simply editing the mailing list file removing or
    adding addresses from or to it.

    As another example, mailing lists defined in LDAP can also be
    used, for example:

    db> add ldap_all_users <"""ldap:///dc=example,dc=edu?mail?sub?(cn=*)"""

    Note the three double-quotes around the LDAP URL. This is
    required.