diff --git a/addons/purchase/purchase.py b/addons/purchase/purchase.py
index 8ba37697c8f..b2d0d173fa9 100644
--- a/addons/purchase/purchase.py
+++ b/addons/purchase/purchase.py
@@ -476,7 +476,7 @@ class purchase_order_line(osv.osv):
                     'date': date_order,
                     })[pricelist]
 
-        qty = 1
+        qty = qty or 1.0
         seller_delay = 0
         for s in prod.seller_ids:
             seller_delay = s.delay
diff --git a/addons/purchase/purchase_view.xml b/addons/purchase/purchase_view.xml
index d0ee536e63c..161f7117090 100644
--- a/addons/purchase/purchase_view.xml
+++ b/addons/purchase/purchase_view.xml
@@ -173,7 +173,7 @@
                     <notebook>
                         <page string="Order Line">
                             <field colspan="4" context="partner_id=parent.partner_id,quantity=product_qty,pricelist=parent.pricelist_id,uom=product_uom,warehouse=parent.warehouse_id" name="product_id" on_change="product_id_change(parent.pricelist_id,product_id,product_qty,product_uom,parent.partner_id, parent.date_order, parent.fiscal_position)"/>
-                            <field name="product_qty"/>
+                            <field context="partner_id=parent.partner_id,quantity=product_qty,pricelist=parent.pricelist_id,uom=product_uom,warehouse=parent.warehouse_id" name="product_qty" on_change="product_id_change(parent.pricelist_id,product_id,product_qty,product_uom,parent.partner_id, parent.date_order, parent.fiscal_position)"/>
                             <field name="product_uom" on_change="product_uom_change(parent.pricelist_id,product_id,product_qty,product_uom,parent.partner_id, parent.date_order)"/>
                             <field colspan="4" name="name"/>
                             <field name="date_planned"/>