diff --git a/addons/mrp_operations/mrp_operations.py b/addons/mrp_operations/mrp_operations.py
index d841e344a9e..f77d5cf839f 100644
--- a/addons/mrp_operations/mrp_operations.py
+++ b/addons/mrp_operations/mrp_operations.py
@@ -354,7 +354,7 @@ class mrp_production(osv.osv):
             for po in self.browse(cr, uid, ids, context=context):
                 direction[po.id] = cmp(po.date_start, vals.get('date_start', False))
         result = super(mrp_production, self).write(cr, uid, ids, vals, context=context)
-        if (vals.get('workcenter_lines', False) or vals.get('date_start', False)) and update:
+        if (vals.get('workcenter_lines', False) or vals.get('date_start', False) or vals.get('date_planned', False)) and update:
             self._compute_planned_workcenter(cr, uid, ids, context=context, mini=mini)
         for d in direction:
             if direction[d] == 1: