diff --git a/addons/crm/wizard/crm_lead_to_opportunity.py b/addons/crm/wizard/crm_lead_to_opportunity.py
index 48097944ec4..f239ad739c1 100644
--- a/addons/crm/wizard/crm_lead_to_opportunity.py
+++ b/addons/crm/wizard/crm_lead_to_opportunity.py
@@ -59,11 +59,11 @@ class crm_lead2opportunity_partner(osv.osv_memory):
 
             if partner_id:
                 # Search for opportunities that have the same partner and that arent done or cancelled
-                ids = lead_obj.search(cr, uid, [('partner_id', '=', partner_id),  ('probability', '<', '100')])
+                ids = lead_obj.search(cr, uid, [('partner_id', '=', partner_id), '|', ('probability', '=', False), ('probability', '<', '100')])
                 for id in ids:
                     tomerge.add(id)
             if email:
-                ids = lead_obj.search(cr, uid, [('email_from', '=ilike', email[0]),  ('probability', '<', '100')])
+                ids = lead_obj.search(cr, uid, [('email_from', '=ilike', email[0]), '|', ('probability', '=', False), ('probability', '<', '100')])
                 for id in ids:
                     tomerge.add(id)