Database migration 5-6

Hello,
Our company is currently using Open ERP 5.0.11. We are planning to migrate towards v6 in the next few weeks. So I set up a new copy of our production database to test the migration process and installed a standalone version of openerp server v6 running on different ports of the server.
Using a v6 client, I am able to connect to the server and retrieve the database list on the v6 server. Connecting to the database though gives an error :
ERROR:db.cursor:Programming error: column ir_module_module.maintainer does not exist
LINE 1: ...dule.menus_by_module,ir_module_module.certificate,ir_module_...
So I noticed your migration module and installed it on my v5 server. After installation of the module, no new menus get created though, even if I see that it should create a sub menu Server Migration under Administration. I don't know what I am missing here.
Am I right in installing the module in the version 5 of my open erp server and connecting using the open erp v5 client? If I try connecting to the v5 database using the open erp v6 server, I get the error above, so I cannot access any menus either!
I'm kind of lost. Any help would be greatly appreciated.
Thanks in advance
Our company is currently using Open ERP 5.0.11. We are planning to migrate towards v6 in the next few weeks. So I set up a new copy of our production database to test the migration process and installed a standalone version of openerp server v6 running on different ports of the server.
Using a v6 client, I am able to connect to the server and retrieve the database list on the v6 server. Connecting to the database though gives an error :
ERROR:db.cursor:Programming error: column ir_module_module.maintainer does not exist
LINE 1: ...dule.menus_by_module,ir_module_module.certificate,ir_module_...
So I noticed your migration module and installed it on my v5 server. After installation of the module, no new menus get created though, even if I see that it should create a sub menu Server Migration under Administration. I don't know what I am missing here.
Am I right in installing the module in the version 5 of my open erp server and connecting using the open erp v5 client? If I try connecting to the v5 database using the open erp v6 server, I get the error above, so I cannot access any menus either!
I'm kind of lost. Any help would be greatly appreciated.
Thanks in advance