Sounds more like the MySQL server is not running.
The upgrade could have overwritten your server startup script.
To see if it's running, in the terminal type 'ps ax' and look for a line with 'safe_mysqld'. if that's not there then mysql server is not running and you'll need to start it.
If it wont start look for a legacy lock file to throw away.
For more specifics there are mailing list archives at:
amp.dynopolis.com