In order to apply Patch 4 on 8.1.7.0 I want to run runInstaller from the Oracle software binaries on the disk rather than from the CD (mainly because for many such odd-hours installs I don't have to be in the server room to change CDs if need comes)

I can't find runInstaller as suggested by Oracle's Patch document on Metalink --
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Start the installer:
If the Installer was installed during the installation of the base 8.1.7.0.0 release, then run the installer from within the $ORACLE_HOME/bin directory.

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Just to make sure, I ran the runInstaller from the CD and "reinstalled" the "Oracle Universal Installer" (location - $ORACLE_HOME) but I still can't find the runIstaller executable.

What am I doing wrong?

Thanks,
-Rajeev