--- mrp.py	2009-11-06 17:20:30.000000000 +0000
+++ mrp.py.old	2009-10-19 15:12:23.000000000 +0100
@@ -261,6 +261,8 @@
         result = []
         result2 = []
         phantom=False
+        # multiplier for child BoMs
+        factor += (bom.product_qty - 1.0)
         if bom.type=='phantom' and not bom.bom_lines:
             newbom = self._bom_find(cr, uid, bom.product_id.id, bom.product_uom.id, properties)
             if newbom:
@@ -295,7 +297,7 @@
                         'hour': float(wc_use.hour_nbr*mult + (wc.time_start+wc.time_stop+cycle*wc.time_cycle) * (wc.time_efficiency or 1.0)),
                     })
             for bom2 in bom.bom_lines:
-                res = self._bom_explode(cr, uid, bom2, factor * bom.product_qty, properties, addthis=True, level=level+10)
+                res = self._bom_explode(cr, uid, bom2, factor, properties, addthis=True, level=level+10)
                 result = result + res[0]
                 result2 = result2 + res[1]
         return result, result2