One last thing,
Needed mod_rewrite to work on IP/~admin/projectX/someUrlRewrite/, having projectX/index.php to rewrite from index.php?url=someUrlRewrite into projectX/someUrlRewrite
To do so, I needed to edit /etc/httpd/conf/httpd.conf and changed "AllowOverride None" to "AllowOverride All" in "<Directory />" tag.
Hum... not quite "out of the box"...