Oracle ODBC Connection Environment

I am using php.exe version 4.0.2 (as cgi) on a WinNT server (SP6a) running IIS. I am unable to connect to an Oracle 8 database running on a Solaris 8 platform via ODBC. I have tried both the Oracle ODBC driver version 8.00.59.00 and the MS Oracle ODBC driver with the same results (ORA-12154: TNS:could not resolve service name). I know the environment variable ORACLE_HOME is set properly since I can display it using the (getenv("ORACLE_HOME") function. I can manually connect to the Oracle 8 database using Access 97 and the same DSN used by my PHP script. So, I feel have eliminated any ODBC Data Source configuration problem. I have eliminated a script problem by connecting to a MS Access database in my script. Are there other environment variables required for a successful connection? Or am I missing something. Thanks, Ron Woods/GAI WR-ALC/LHA (OL-SA) Kelly AFB TX 78241 DSN: 945-7945 COM: 210-925-7945