Entries encoding by line

When I encode entries directly in the journal I get this error :

Traceback (most recent call last):
  File "/home/cecile/openerp/trunk/server/bin/netsvc.py", line 410, in run
    r = m(*msg[2:])
  File "/home/cecile/openerp/trunk/server/bin/service/web_services.py", line 368, in execute
    res = service.execute(db, uid, object, method, *args)
  File "/home/cecile/openerp/trunk/server/bin/osv/osv.py", line 107, in execute
    res = pool.execute_cr(cr, uid, obj, method, *args, **kw)
  File "/home/cecile/openerp/trunk/server/bin/osv/osv.py", line 85, in execute_cr
    return getattr(object, method)(cr, uid, *args, **kw)
  File "/home/cecile/openerp/trunk/server/bin/addons/account/account_move_line.py", line 469, in onchange_partner_id
    if val['account_id']:
KeyError: 'account_id'

cecile@pearl:~/openerp/trunk/server$ cd ../addons/
cecile@pearl:~/openerp/trunk/addons$ bzr version-info
revision-id: <email address hidden>
date: 2008-12-18 11:54:15 +0100
build-date: 2008-12-18 15:00:28 +0100
revno: 2043
branch-nick: addons