diff --git a/base/admin.py b/base/admin.py
index 37e400946..99f81f8af 100644
--- a/base/admin.py
+++ b/base/admin.py
@@ -1,8 +1,8 @@
 from django.contrib import admin
+from django.core.urlresolvers import reverse
 
 from base.models import ProblemaMigracao
 from sapl.utils import register_all_models_in_admin
-from django.core.urlresolvers import reverse
 
 register_all_models_in_admin(__name__)
 
@@ -15,8 +15,11 @@ class ProblemaMigracaoAdmin(admin.ModelAdmin):
                     "descricao", "get_url"]
 
     def get_url(self, obj):
-        info = (obj._meta.app_label, obj._meta.model_name)
-        endereco = reverse('admin:%s_%s_change' % info, args=(obj.pk,))
+
+        info = (obj.content_object._meta.app_label,
+                obj.content_object._meta.model_name)
+        endereco = reverse('admin:%s_%s_change' % info,
+                           args=(obj.content_object.pk,))
         return "<a href='%s'>%s</a>" % (endereco, endereco)
 
     get_url.short_description = "Endereço"
diff --git a/base/migrations/0014_auto_20160502_1635.py b/base/migrations/0014_auto_20160502_1635.py
new file mode 100644
index 000000000..6fbae0bb9
--- /dev/null
+++ b/base/migrations/0014_auto_20160502_1635.py
@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.5 on 2016-05-02 19:35
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('base', '0013_remove_problemamigracao_endereco'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='problemamigracao',
+            name='descricao',
+            field=models.CharField(default='', max_length=300, verbose_name='Descrição'),
+            preserve_default=False,
+        ),
+        migrations.AlterField(
+            model_name='problemamigracao',
+            name='problema',
+            field=models.CharField(default='', max_length=300, verbose_name='Problema'),
+            preserve_default=False,
+        ),
+    ]
diff --git a/base/models.py b/base/models.py
index 9a94c9eb8..f1fb3811f 100644
--- a/base/models.py
+++ b/base/models.py
@@ -2,6 +2,7 @@ from django.contrib.contenttypes.fields import GenericForeignKey
 from django.contrib.contenttypes.models import ContentType
 from django.db import models
 from django.utils.translation import ugettext_lazy as _
+
 from sapl.utils import UF
 
 
@@ -53,10 +54,8 @@ class ProblemaMigracao(models.Model):
                                      verbose_name=_('Tipo de Content'))
     object_id = models.PositiveIntegerField(verbose_name=_('ID do Objeto'))
     content_object = GenericForeignKey('content_type', 'object_id')
-    problema = models.CharField(max_length=300, null=True,
-                                verbose_name=_('Problema'))
-    descricao = models.CharField(max_length=300, null=True,
-                                 verbose_name=_('Descrição'))
+    problema = models.CharField(max_length=300, verbose_name=_('Problema'))
+    descricao = models.CharField(max_length=300, verbose_name=_('Descrição'))
     eh_stub = models.BooleanField(verbose_name='É stub?')
 
     class Meta:
diff --git a/legacy/migration.py b/legacy/migration.py
index d69da781c..ddc8e0bfd 100644
--- a/legacy/migration.py
+++ b/legacy/migration.py
@@ -5,7 +5,6 @@ import yaml
 from django.apps import apps
 from django.apps.config import AppConfig
 from django.core.exceptions import ObjectDoesNotExist
-from django.core.urlresolvers import reverse
 from django.db import connections, models
 from django.db.models import CharField, TextField
 from django.db.models.base import ModelBase
@@ -14,7 +13,6 @@ from model_mommy.mommy import foreign_key_required, make
 
 from base.models import ProblemaMigracao
 from comissoes.models import Composicao, Participacao
-from materia.models import TipoMateriaLegislativa
 from parlamentares.models import Parlamentar
 from sessao.models import SessaoPlenaria
 
diff --git a/materia/migrations/0030_auto_20160502_1630.py b/materia/migrations/0030_auto_20160502_1630.py
new file mode 100644
index 000000000..6f8fd60be
--- /dev/null
+++ b/materia/migrations/0030_auto_20160502_1630.py
@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.5 on 2016-05-02 19:30
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('materia', '0029_merge'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='materialegislativa',
+            name='tipo_origem_externa',
+            field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='tipo_origem_externa_set', to='materia.TipoMateriaLegislativa', verbose_name='Tipo'),
+        ),
+    ]