Http://www.cnblogs.com/flyingis/archive/2008/01/22/1048354.html
The direct connection methods are basically the same. I wrote an article "ArcIMS 9.2 direct connection to ArcSDE for SQL Server 2005 Express". The following lists the direct connection methods of ArcSDE 9.2 For Oracle10g, if the connection is tested in ArcIMS author SDE connection or no response is returned, check the connection with the following steps.
1. Prepare the operating system required by the symbol
2. Install Oracle10g compliant with ArcSDE 9.2, for example, oracle10.2.0.2 on Windows, oracle10.2.0.2/10.2.0.3 on Linux/Unix
3. Install ArcSDE 9.2 and ArcIMS 9.2 (the installation methods under various operating systems are not described here)
4. ArcSDE 9.2 post installation creates users, tablespaces, and SDE services. The SDE service can be stopped so far.
5. Configure the following environment variables on the ArcIMS server:
Sdehome % arcimshome %/server (Linux/Unix: sdehome $ arcimshome/Server)
PATH % sdehome %/bin (Linux/Unix: path $ sdehome/bin)
6. Install the Oracle10g client, configure the net service name (such as orcl), and test the connection.
7. ArcIMS author SDE connection parameters:
Instance SDE: Oracle10g
Username SDE
Password SDE password @ orcl
Make sure that all the above steps are configured successfully, and the rest is "connection successful" waiting for you.