# to install email notification hook
from django.contrib.contenttypes.models import ContentType
from django.contrib.comments.models import Comment
from django.dispatch import dispatcher

# Email hook 
def post_YOURMODEL_comment_save(sender,instance):
    if instance.content_type == ContentType.objects.get_for_model(YOURMODEL):
        ym=instance.get_content_object()
        from django.core.mail import send_mail
        from django.template import Context, loader
        subject = 'New Comment by %s on %s'%(instance.user.username,ym.title)
        message_template = loader.get_template('email/comment_notification_email.txt')
        message_context = Context({ 'comment':instance,"content_object":ym})
        message = message_template.render(message_context)
        send_mail(subject, message,settings.DEFAULT_FROM_EMAIL,[ym.user.email])
dispatcher.connect(post_YOURMODEL_comment_save, sender=Comment, signal=models.signals.post_save)