@dc_freak : it's recommended to do it on a local server - For installing a web server, I think there is an article in the Knowledge database
@Mike Barlow : It depends on how IB Team modified the database. If there is no modification at all in the database, it should work too with IB 1.3
I look arount IB site and I do not found a lot of details for IB 1.3 so I guess that it's just modification of php files and no modification of the database...
So you can try to run the converter and see if it works or not...