[PHP-INSTALL] SQL Server connection problem

[RJahanzeb]

I am trying to run PHP using iPlanet 6.0 which connects to the SQL Server 2000. I have this working on my development server. On production server I get the following error.
Warning: mssql_connect(): Unable to connect to server: (servername).

Following is working already.
Connection from development server to the same database server with same username and password.
Running PHP on the production server.
JSP sample to connect to the same database from the production server.

I also ran the PHPInfo on both servers to see if anything was obviously different.

Please help,
Rachna