diff --git a/openerp/addons/base/res/res_partner.py b/openerp/addons/base/res/res_partner.py
index 22cd4a8d66a..7d357ed0c9e 100644
--- a/openerp/addons/base/res/res_partner.py
+++ b/openerp/addons/base/res/res_partner.py
@@ -508,6 +508,14 @@ class res_partner(osv.osv, format_address):
             if not parent.is_company:
                 parent.write({'is_company': True})
 
+    def unlink(self, cr, uid, ids, context=None):
+        orphan_contact_ids = self.search(cr, uid,
+            [('parent_id', 'in', ids), ('id', 'not in', ids), ('use_parent_address', '=', True)], context=context)
+        if orphan_contact_ids:
+            # no longer have a parent address
+            self.write(cr, uid, orphan_contact_ids, {'use_parent_address': False}, context=context)
+        return super(res_partner, self).unlink(cr, uid, ids, context=context)
+
     def write(self, cr, uid, ids, vals, context=None):
         if isinstance(ids, (int, long)):
             ids = [ids]