Oracle connection error: ORA-12441: TNS:no listener in Spotlight on RAC (21830)

I have attempted to install and configure Spotlight on RAC but am having trouble discovering the target database. I receive the following error (see attached image001.gif):

Oracle connection error: ORA-12441: TNS:no listener

I've created a QUEST user with DBA privileges and can make a remote connection through sqlplus, so I do not believe that this is a listener problem.

Incorrect Port/Host

Verify that the Hostname and Port number found in the Oracle RAC TNS entry match the Hostname and Port number used by Spotlight on RAC.

1. In Spotlight on RAC Connection Manager, double click the Spotlight on RAC connection icon to connect to the Oracle RAC
2. When the "Verify Cluster Connection Details" window opens, verify Hostname and Port numbers in the grid match the TNS entries for the Oracle RAC
3. If necessary, click in the Host or Port fields to make necessary corrections
4. Click the Test button to verify details