diff --git a/bin/addons/base/ir/ir.xml b/bin/addons/base/ir/ir.xml
index 0f164e637df..8bcb3abfced 100644
--- a/bin/addons/base/ir/ir.xml
+++ b/bin/addons/base/ir/ir.xml
@@ -750,10 +750,8 @@
                                     <group colspan="2" col="2">
                                         <separator string="Field Type" colspan="2"/>
                                         <field name="ttype" select="2"/>
-                                        <field name="relation" attrs="{'required': [('ttype','in',['many2one','one2many','many2many'])],
-                                                                                  'readonly': [('ttype','!=','one2many'), ('ttype','!=','many2one'), ('ttype','!=','many2many')]}"/>
-                                        <field name="relation_field" attrs="{'required': [('ttype','=','one2many')],
-                                                                             'readonly': [('ttype','!=','one2many')]}"/>
+                                        <field name="relation" attrs="{'required': [('ttype','in',['many2one','one2many','many2many'])],'readonly': [('ttype','!=','one2many'), ('ttype','!=','many2one'), ('ttype','!=','many2many')]}"/>
+                                        <field name="relation_field" attrs="{'required': [('ttype','=','one2many')], 'readonly': [('ttype','!=','one2many')]}"/>
                                         <field name="selection" attrs="{'required': [('ttype','in',['selection','reference'])], 'readonly': [('ttype','not in',['selection','reference'])]}"/>
                                         <field name="size" attrs="{'required': [('ttype','in',['char','reference'])], 'readonly': [('ttype','not in',['char','reference'])]}"/>
                                         <field name="state"/>
diff --git a/bin/addons/base/ir/ir_model.py b/bin/addons/base/ir/ir_model.py
index 05fe09d2b87..105ffece9dc 100644
--- a/bin/addons/base/ir/ir_model.py
+++ b/bin/addons/base/ir/ir_model.py
@@ -243,9 +243,14 @@ class ir_model_fields(osv.osv):
         if vals.get('state','base') == 'manual':
             if not vals['name'].startswith('x_'):
                 raise except_orm(_('Error'), _("Custom fields must have a name that starts with 'x_' !"))
-            if self.pool.get(vals['model']):
-                self.pool.get(vals['model']).__init__(self.pool, cr)
-                self.pool.get(vals['model'])._auto_init(cr, {})
+            
+            model_ids = self.pool.get('ir.model').search(cr, user, [('model','=',vals['relation'])])
+            if model_ids:
+                if self.pool.get(vals['model']):
+                    self.pool.get(vals['model']).__init__(self.pool, cr)
+                    self.pool.get(vals['model'])._auto_init(cr, {})
+            else:
+                raise except_orm(_('Error'), _("Model %s Does not Exist !" % vals['relation']))
         return res
 ir_model_fields()