SQL*Net V2.1 ERROR: ORA-12500: TNS:listener failed to start a dedicated server process

Hi,

   I think I have SQL*Net V2.1 installed, but when I try to connect to an Oracle DB on the same host as the client with "sqlplus /_at_tomahawk", I get:

        ERROR: ORA-12500: TNS:listener failed to start a dedicated server process

This could be caused by an incorrectly set up environment according to the error manual. I'm just wondering, other than TNS_ADMIN, what environmental variables and Oracle initialization parameters must be set to use SQL*Net V2 ?

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        Michael D. Grapevine 
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