ORA8.1.5, Apache, W2K Problem

[wxdqz]

My system/client :
- Windows 2000 Pro
- Oracle 8.1.5 Client (with OCI)
- Apache 3.1.12
- PHP 4.0.2
Server :
- Windows 2000 Pro
- Oracle 8.1.5 Server

I can connect my server with SQL*Plus and working fine with IIS5.
I changed my web server using Apache but it can't connect to Oracle Server.
Message :
Warning: _oci_open_server: ORA-06401: NETCMN: invalid driver designator in .....

PHP script :
<?
..
..
$db_user="sekretariat";
$db_pass="sekretariat";
$db_name="ora2000";

$connection = OCILogon($db_user, $db_pass,$db_name)
or die("Database tidak dapat digunakan ...");
..
..
?>

Anybody help me ??? Thank's