This describes how to use mlmmj with openSMTPd and eQmail. It is assumed that you are familiar with both MTA's so far that they are up and running as well you read the mlmmj documentation or at least have it on site. There is mentioned eQmail always, but the instuctions are valid for qmail-1.03 and netqmail too.
And why two MTA's with one mailing list manager in one place?
First there are some name conventions which will be used further:
From this the list address is  support@lists.dyndn.es  
. The list itself calls  user-support 
(like the list owners name) and the home directory for now is  /home/mails/user-support 
(this will be change sligthly later on).
/*
It is urgently recommended to use not a “+” or “-” sign in the user part of the list address. It is explained later on why.
*/
It is assumed that all mlmmj binaries are located in  /usr/local/bin  
. If user vmu and/or group vmg doesn't exist on the system it is recommended to create them before proceed:
groupadd -g 65002 vmg useradd -u 65001 -g 65002 -s /bin/nologin vmu
The UID and GID will be used later on. Alternative nobody/nogroup can be used too.
Before we start lets do a few thoughs about the organisation of lists. First let's see how mlmmj works. To create a new list there is the command  mlmmj-make-ml  
, which creates a folder named by <listowner> (here  user-support  
) with the necessary files and folders of a list inside a spooldir (here  /home/mails  
).
In case that there is or will be more than one mailing list it is a good idea, to put all mailinglists in a subfolder (here  lists  
). The reason is that we have to create a cron job for maintenance later on. Usually there is one maintenance job for each list needed, by using a separate  lists 
folder we can do one job for all lists. For this mandatory recommendation we create  /home/mails/lists 
as spooldir:
mkdir /home/mails/lists
So from now on, the home directory of user-support is changed to  /home/mails/lists/user-support  
.
/*
To include this mandatory recommendation there have to be the  lists 
folder added to the path of the home directory, like  /home/mails/lists/user-support  
.
creates the folders and files for a new mailinglist. The full command with the definitions above would be
/usr/local/bin/mlmmj-make-ml -L user-support -s /home/mails
All needed files and folders will be created directly in  /home/mails/user-support  
, the home directory of the list owner.
*/
To get a cleaner structure it is maybe a good idea too, to use a subfolder  Listdir 
inside the home of the list owner. This can be compared with Maildir, which separates its structure in a folder by default. Files like  .forward 
and/or  .qmail 
and similar ones can then (later on) be created outside the list directory. But for this we have to create the list owners home directory before we create the list itself:
mkdir -p /home/mails/lists/user-support /usr/local/bin/mlmmj-make-ml -L Listdir -s /home/mails/lists/user-support
Add a new user  user-support 
to the user table:
user-support 65001:65002:/home/mails/lists/user-support
and an alias to the aliases table:
support: user-support
Create a dot-forward file in the home directory of user-support:
echo "|/usr/local/bin/mlmmj-recieve -F -L /home/mails/lists/user-support/Listdir" > /home/mails/user-support/.forward
Add a new user to  /var/qmail/users/assign  
:
+user-support:user-support:65001:65002:/home/mails/lists/user-support:::
and create a new alias
echo "user-support" >> /var/qmail/alias/.qmail-support
Create a dot-qmail file in the home directory of user-support
echo "|/usr/local/bin/mlmmj-recieve -F -L /home/mails/lists/user-support/Listdir" > /home/mails/user-support/.qmail
  Do not use dot-forward or preline in the  ~/.qmail 
file! This will not work properly!
While mlmmj and openSMTPd uses the “+” (plus) sign as delimiter of address extensions on default, eQmail uses a “-” (minus) sign. So there are no changes necessary for openSMTPd, but three different ways to handle it with eQmail. Only one of them can be used at the same time.
Create a file  delimiter 
in the control directory of the list:
echo "-" > /home/mails/user-support/Listdir/control/delimiter
On the first view this seems to be the easiest way. But the disadvantage is that the texts of mlmmj still contains the “+” sign. Means the information contains wrong mail addresses. The texts can be changed manually, but there perhaps situations that this have to be reverted or will be reverted by e.g. an update.
Nevertheless we need one more alias to handle all address extensions. In the qmail alias folder do;
ln -s .qmail-support .qmail-support-default
As of the way how eQmail handles aliases these necessary ones have to be created (exactly so):
cd /var/qmail/alias ln -s .qmail-support .qmail-support+subscribe ln -s .qmail-support .qmail-support+subscribe-default ln -s .qmail-support .qmail-support+confsub-default ln -s .qmail-support .qmail-support+unsubscribe ln -s .qmail-support .qmail-support+confunsub-default ln -s .qmail-support .qmail-support+help ln -s .qmail-support .qmail-support+get-default ln -s .qmail-support .qmail-support+faq ln -s .qmail-support .qmail-support+owner
This looks like much more work like changing the delimmiter of mlmmj, but it isn't. The advantage is that the mailing list can be used by eQmail and openSMTPd without any changes. For subscribes are two aliases necessary,  .qmail-<LISTNAME>+subscribe 
and  .qmail-<LISTNAME>+subscribe-default  
. The first one is to subscribe to the regular list through address <LISTNAME>+subscribe, the second one (with suffix “-default”) is a.o. for address <LISTNAME>+subscribe-digest. At least there have to be an alias for every address extension delimited by a “+” sign, although if it will be disabled by mlmmj later on.
The delimiter for address extensions (eQmail uses the term user extensions) is configurable through the eQmail sources. Edit the file  conf-break 
and change the delimiter to “+”. Afterwards recompile and reinstall eQmail. This way should be used by more experienced users.
The virtual users of the MTA's have to be the owner of the list with read/write access. As they are mapped to the id's of vmu:vmg:
cd /home/mails/lists chown -R vmu:vmg user-support
It is recommended to create a scheduled maintenance job by the mlmmj docs for each list by default. This can be done with one job for all lists if they are inside a folder directly. As we use a  Listdir 
we have to create a new folder and a symlink:
$ cd /home/mails/lists $ mkdir maintenance $ cd maintenance $ ln -s ../user-support user-support
Create a link for each mailinglist. Thus a cronjob will be like
0 */2 * * * /usr/bin/mlmmj-maintd -F -d /home/mails/lists/maintenance
This is just a recommendation. There are other solutions possible to do the maintenance job also. For one list simply do
0 */2 * * * /usr/bin/mlmmj-maintd -F -L /home/mails/lists/user-support/Listdir
Last but not least there are some options, so called tunables, for better list control. Some of them are highly recommended, others more or less important. Some examples:
ls -1 /home/mails/lists/user-support/Listdir/control delimiter footer listaddress nonomailsub owner subonlypost
Many of them are boolean, means a functionality will be turned on if a file exists (e.g.  subonlypost  
). In practise it is perhaps a good idea to put the description inside, so we don't have to refer back to the documentation in any case. Also, creating a folder inside  control 
and moving boolean files into it or back makes it easy to switch a functionality on or off quite quickly.
After the wished configuration is done it is time to test it. Assuming the address extension delimiter is “+”, do:
Troubleshooting hints:
 Listdir/archive 
and set the  index 
to 0There is another thing to mention that could be happen: if there is an exim MTA somewhere on the way - e.g. a ISP relay MTA or the recipients (subscribers) MTA - maybe some mails with address extensions will bounce. This affects e.g. subscribe confirmation mails, where the sender address is like
         <LISTNAME>+bounces-confsub-123456790ABCDEF-user=example.com@lists.dyndn.es 
Perhaps the reason is that these exim MTA's have to be configured for mlmmj through  mlmmj_router 
and/or  mlmmj_transport 
(see mlmmj documentation).