UUID pk MultiValueDictKeyError

# the bug is described here http://code.djangoproject.com/ticket/12235
# I tried to use the django-extensions implementation of UUIDField(), I have the same bug
# opened this issue for django-extensions 
# https://github.com/django-extensions/django-extensions/issues#issue/50
# 
# I'm new to django, I just suspect that there is some code in django-admin inlines which 
# assumes integer primary keys

# using : django 1.2.3 , django-extensions 0.5, PGSQL db with psycopg2

# ==============
# in settings.py
# ==============

INSTALLED_APPS = (
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.sites',
    'django.contrib.messages',
    'django.contrib.admin',
    'django_extensions',
    'myapp',
)

# ==================
# in myapp/models.py 
# ==================

from django.db import models
from django.db.models import CharField
from django_extensions.db.fields import UUIDField

try:
    import uuid
except ImportError:
    from django_extensions.utils import uuid

class Worker(models.Model):
    id = UUIDField(primary_key=True)
    other_uuid_not_pk = UUIDField()
    name = models.CharField(blank=True, max_length=100)
    def __unicode__(self):
        return(self.name)

class Task(models.Model):
    id = UUIDField(primary_key=True)
    other_uuid_not_pk = UUIDField()
    description = models.CharField(blank=True, max_length=100)
    workers = models.ManyToManyField(Worker, through="Todo")
    def __unicode__(self):
        return(self.description)

class Todo(models.Model):
    id = UUIDField(primary_key=True)
    other_uuid_not_pk = UUIDField()
    worker = models.ForeignKey(Worker)
    task = models.ForeignKey(Task)
    time_allowed = models.IntegerField(default=1)

# =================
# in myapp/admin.py 
# =================

from django.contrib import admin
from myapp.models import *

class WorkerAdmin(admin.ModelAdmin):
    pass

class TodoInline(admin.TabularInline):
    model = Todo
    fk_name = 'task'
    raw_id_fields = ('worker',)
    extra = 1
    
class TaskAdmin(admin.ModelAdmin):
    inlines = (TodoInline,)

admin.site.register(Worker,WorkerAdmin)
admin.site.register(Task,TaskAdmin)

# Once synced and admin urls setup, foillow these steps to reproduce the bug :
# 1. Log into admin, add some workers
# 2. Go to Task admin, add a task, add a related worker to it, save
# 3. Go back to this same task admin page, and just try to save again, or add a worker and save, you got :
# 
# MultiValueDictKeyError at /admin/myapp/task/c64af3b5-f6e4-11df-869c-001cb3bc281a/
# "Key 'todo_set-0-id' not found in <QueryDict: .....>"
#