title: Django Admin inline for recursive ManyToMany
body: <p>I have the following model with a many-to-many relationship to itself</p>
  
  <pre><code>class Ticket(models.Model):
  
      STATUS = (
          (0, "Open"),
          (1, "Closed"),
      )
      status = models.SmallIntegerField(default=0,choices=STATUS)
      title = models.CharField(max_length=100)
      replies = models.ManyToManyField('self')
      description = models.TextField()
  </code></pre>
  
  <p>i am trying to display this model as an inline in the admin, using the following code</p>
  
  <pre><code>class TicketReply(admin.TabularInline):
      model = Ticket.replies.through
  </code></pre>
  
  <p>however i keep getting this error</p>
  
  <pre><code>&lt;class 'tsn.ticket.models.Ticket_replies'&gt; has more than 1 ForeignKey to &lt;class 'tsn.ticket.models.Ticket'&gt;
  </code></pre>
  
  <p>so im i doing this wrong, or is this not supported ?</p>