Rather than restrict you to a single email address (‘user@host’), qmail in the default setup gives you control over an infinite number of addresses ‘user-*@host’. Of course, you (normally) have no way of controlling ‘elsewhere@host’ since that could lead to overlap between users' ‘e-mail address space’. As a consequence, all you mailing lists have to be named ‘user-xx@host’ where ‘user’ is your user name and ‘xx’ is anything. You cannot create e.g. ‘mylist@host’, only ‘user-mylist@host’. To create the list ‘user-list@host’ do:
% ezmlm-make ~/list ~/.qmail-list user-list host
Notice that ‘user’ is not part of the .qmail file name.
There are two way to create lists with names not starting with your user name: First, qmail can be set up so that you control a virtual domain (see below). Second, the system administrator can set up lists with arbitrary names within the ~alias/ directory.