Classes
-------

In versions of ProFTPD prior to 1.2.10rc1, a proftpd.conf that used Classes
might look like:

  ...

  Classes on
  Class foo ip 127.0.0.1
  Class foo regex *.evil.com
  Class foo limit 10

  ...
 
The new Class code uses <Class> sections.  The above configuration would
thus be:

  <Class foo>
    From 127.0.0.1
    From *.evil.com
  </Class>

The Class and Classes configuration directives are deprecated.  The new
<Class> sections do not support the old "limit" keyword.  Instead,
a new MaxClientsPerClass configuration directive can be used:

  MaxClientsPerClass foo 10

There is no equivalent for the old "Class" directive.  The proftpd engine
will always try to determine if the connecting client belongs to a defined
class.  No class definitions means that classes will not be used.

Classes can only be defined in the "server config" context, not on a <Global>
or per-<VirtualHost> basis.  This is because the class for a client is
determined as soon as the client connects to the server, before the server
determines which <VirtualHost> the client is trying to reach.  Therefore,
class definitions always apply to the entire server.