class SendRecv {
   send{}
   recv{}
}

class Server {
  use base qw(SendRecv)
  ....
}

##</code><code>##

class SendRecv {
   send{}
   recv{}
   new{}
}

class Server {
  use SendRecv;

  new { 
    my $sr = SendRecv->new();
    bless $class, { pool => [$sr] } 
  }
  ....
}