localhost issue on leopard

I created a database with mysql but was unable to connect to it from wp-admin/install.php. I created different users, flushed privileges, all to no avail. Then I tried changing db_host in wp-config.php from ‘localhost’ to ‘127.0.0.1’. This solved the problem.

I’m using virtual hosts in my local development environment. The entry for localhost aliases to 127.0.0.1, as it always did.

I wasted about a half hour with this so I hope this helps somebody.
I’d like to understand why I can’t use localhost instead of the ip though. I think this information should go into the wordpress installation guide.