diff --git a/bin/addons/base/ir/ir_model.py b/bin/addons/base/ir/ir_model.py
index 40c12461bc8..ffb2d31b909 100644
--- a/bin/addons/base/ir/ir_model.py
+++ b/bin/addons/base/ir/ir_model.py
@@ -260,6 +260,8 @@ class ir_model_fields(osv.osv):
         if 'model_id' in vals:
             model_data = self.pool.get('ir.model').browse(cr, user, vals['model_id'])
             vals['model'] = model_data.model
+        if context is None:
+            context = {}
         if context and context.get('manual',False):
             vals['state'] = 'manual'
         res = super(ir_model_fields,self).create(cr, user, vals, context)
@@ -267,7 +269,7 @@ class ir_model_fields(osv.osv):
             if not vals['name'].startswith('x_'):
                 raise except_orm(_('Error'), _("Custom fields must have a name that starts with 'x_' !"))
 
-            if 'relation' in vals and not self.pool.get('ir.model').search(cr, user, [('model','=',vals['relation'])]):
+            if vals.get('relation',False) and not self.pool.get('ir.model').search(cr, user, [('model','=',vals['relation'])]):
                  raise except_orm(_('Error'), _("Model %s Does not Exist !" % vals['relation']))
 
             if self.pool.get(vals['model']):
diff --git a/bin/osv/orm.py b/bin/osv/orm.py
index 6a96f22ff40..76bca677224 100644
--- a/bin/osv/orm.py
+++ b/bin/osv/orm.py
@@ -276,7 +276,7 @@ class browse_record(object):
                     else:
                         new_data[n] = data[n]
                 self._data[data['id']].update(new_data)
-        
+
         if not name in self._data[self._id]:
             #how did this happen?
             self.logger.notifyChannel("browse_record", netsvc.LOG_ERROR,
@@ -438,7 +438,7 @@ class orm_template(object):
                 'name': k,
                 'field_description': f.string.replace("'", " "),
                 'ttype': f._type,
-                'relation': f._obj or 'NULL',
+                'relation': f._obj or '',
                 'view_load': (f.view_load and 1) or 0,
                 'select_level': tools.ustr(f.select or 0),
                 'readonly':(f.readonly and 1) or 0,