Many to many relation does not respect softdeletion

[basask]

The problem seems to be in many to many scenarios.
Below a snippet on how to reproduce (untested)

# models
from softdelete.models import SoftDeleteModel

class ModelA(SoftDeleteModel):
    name = models.CharField(max_length=16)

class ModelB(SoftDeleteModel):
    name = models.CharField(max_length=16)

class M2M(SoftDeleteModel):
    left = model.ForeignKey(ModelA, related_name='right')
    right = model.ForeignKey(ModelB, related_name='left')

# test
mA = ModelA.objects.create(name='A')
mB = ModelB.objects.create(name='B')
M2M.objects.create(left=mA, right=mB)

mB.objects.filter(left__left__name='A').count()
# Thats ok. Only one instance found here

M2M.objects.all().delete()

mB.objects.filter(left__left__name='A').count()
# Still finding objects when should be hiding through softdelete