[5.0] ICS random generator is predicable

[Christophe CHAUVET]

Server revno: 1755
Addons revno: 2268
Client revno: 953

The random generator give a non unique sequence must required on ICS File

--------------8<---------------8<-------------
select name,code from crm_case where code='OpenERP-8755374812';
                       name | code
-----------------------------------------------------+--------------------
First meeting | OpenERP-8755374812
OpenERP Install | OpenERP-8755374812
OpenERP Prospect | OpenERP-8755374812
--------------8<---------------8<-------------

Distribution: Ubuntu
Version: 8.10 (intrepid)
Python 2.5.2

Locale:
  LANG=fr_FR.UTF-8