Problem with istallation in subdirectory

Hello all,
tried 1.5-beta-1 2005-01-07 and installed locally on my computer without problem, but when I install in a subdirectory on my web server I can’t get WordPress to understand that it’s in a sub directory. I have manually edited the “home” and “blog url” (or similar) in phpmyadmin, and manually typed the path to my wordpress admin page, and that is displayed (without theme or CSS) but all links to options in the menu is still pointing to the root instead of my sub directory. Also, the value for the url it is changed back in the data base to be empty! Also tried to change the “WordPress address (URI)” in the wordpress admin interface, with the same result.
I’m I missing something obvious?!?
//Robert