Charset for postgreSQL DB-adapter is not valid

Charset in connection-settings when using Pdo_pgsql is not valid.

As long as you do not enter anything in the charset-field when creating the adapter, all is good.
But, entering a charset, save it, and the adapter will fail with an exception, since, charset is not a valid conneciton-setting.

But if you then delete the contents of the charset-field again, it is still saved in the connection-settings for the adapter, making it fail to connect still.