title: Django - Cascade deletion in ManyToManyRelation
body: <p>Using the following related models (one blog entry can have multiple revisions):</p>
  
  <pre><code>class BlogEntryRevision(models.Model):
      revisionNumber = models.IntegerField()
      title = models.CharField(max_length = 120)
      text = models.TextField()
      [...]
  
  class BlogEntry(models.Model):
      revisions = models.ManyToManyField(BlogEntryRevision)
      [...]
  </code></pre>
  
  <p>How can I tell Django to delete all related <code>BlogEntryRevision</code>s when the corresponding <code>BlogEntry</code> is deleted? The default seems to be to keep objects in a many-to-many relation if an object of the "other" side is deleted. Any way to do this - preferably without overriding <code>BlogEntry.delete</code>?</p>