Sorry about the confusion Sam....I completely missed the fact that the user had updated the tnsnames.ora before trying the connection.

If this is true then I find it hard to believe how the connection was made; Without tnsnames.ora where does the PORT number information comes from ???

So back to the original poster of the message...
Are you sure there is only one tnsnames.ora on your local system (from where you are launching tnsping) not on the server.

One way to test will be rename one of the service names in your tnsnames.ora and try connecting with the NEW name; this will make sure that this is the tnsnames.ora in use.

- Rajeev