To get the OCI driver to work on an Linux OS you have add the Oracle library to
enviroment variable LD_LIBRARY_PATH. The easiest way to do this without
screwing up the OS or to hack Coldfusion Runtime user's profile is to edit the
file "/etc/init.d/coldfusionmx7". Search the line "OS=Linux". The next line
will set the environmental variable LD_LIBRARY_PATH, append the directory for
Oracle library, e.g. "<OracleHome>/lib". Restart coldfusion and you should be
able to connect to the database.

Note: this could work for other unix OS, e.g. solaris.