When installing 4.0 beta I chose default settings most of the way, English Australia language, import ezwebin, map missing languages to Eng/Au. At the last step I chose not to notify eZ of the installation and received:

Fatal error: A database transaction in eZ Publish failed.

The current execution was stopped to prevent further problems.
You should contact the System Administrator of this site with the information on this page.
The current transaction ID is TRANSID-bd4faf747a30bb0a22784e4617b741ca and has been logged.
Please include the transaction ID and the current URL when contacting the system administrator.

See attached file for overview of entire output.