Hello,
as far as i can tell you from Oracle Net8,you need an installation of Net8 Client on the webserver. With Net8 Assistant you create a logical database name which point via TCP/IP to your oracle database. You will find this configuration in a file called tnsnames.ora. With Net8 Assistant you can also test your connection maybe with user scott/tiger. Be sure that your path variable(NT) points to the oracle_home folder.
Excuse my bad englisch.
Joerg