[Trunk]Problem in product on_change method in sale_margin

Steps to reproduce:
1) Install sale_margin module
2) Create a SO Open the So line you have faced the following traceback.

Traceback (most recent call last):
  File "/home/amp/workspace/trunk6/server/openerp/osv/osv.py", line 118, in wrapper
    return f(self, dbname, *args, **kwargs)
  File "/home/amp/workspace/trunk6/server/openerp/osv/osv.py", line 172, in execute
    res = self.execute_cr(cr, uid, obj, method, *args, **kw)
  File "/home/amp/workspace/trunk6/server/openerp/osv/osv.py", line 163, in execute_cr
    return getattr(object, method)(cr, uid, *args, **kw)
TypeError: product_id_change() takes at most 18 arguments (19 given)

Solution : the context is missing in product_id_change method is sale.order.line object.

=== modified file 'sale_margin/sale_margin.py'
--- sale_margin/sale_margin.py 2011-07-01 23:41:24 +0000
+++ sale_margin/sale_margin.py 2011-07-13 07:33:37 +0000
@@ -25,7 +25,7 @@

     def product_id_change(self, cr, uid, ids, pricelist, product, qty=0,
             uom=False, qty_uos=0, uos=False, name='', partner_id=False,
- lang=False, update_tax=True, date_order=False, packaging=False, fiscal_position=False, flag=False):
+ lang=False, update_tax=True, date_order=False, packaging=False, fiscal_position=False, flag=False, context=None):
         res = super(sale_order_line, self).product_id_change(cr, uid, ids, pricelist, product, qty=qty,
             uom=uom, qty_uos=qty_uos, uos=uos, name=name, partner_id=partner_id,
             lang=lang, update_tax=update_tax, date_order=date_order, packaging=packaging, fiscal_position=fiscal_position, flag=flag)