Drupal 6 on 1and1.com
I created the MySQL db (mySQL Version 5) and uploaded the files for the site to a folder that was alone on a subdomain.
I hit the site, the first step asked me to select a language. The next screen gave me an error saying that register_globals needed to be disabled.
I checked .htaccess in the root and for php 5 register_globals was set to 0.
After trying a handful of different things, all I needed to do was create a file called php.ini and add it to the root of the site. It only has 1 line of text:
register_globals = off
I found this on a Drupal.org comment here.
hopefully this saves at least one other person some grief.
2008.03.03 UPDATE: I kept running out of memory so I added the following line to php.ini:
memory_limit = 40M
I don't have a good reason to pick 40M, it seems to be running fine now though.
2008.10.19 UPDATE: I am installing Uberart 1.5 Deluxe (running Drupal 5.11) and the same php.ini file was required.