$charSet is actually defined in [adodb.inc.php](https://github.com/ADOdb/ADOdb/blob/master/adodb.inc.php#L385), but the default value is *false*. Overriding the default value should be fine though; with regards to 'iso_1' vs something else, have you considered UTF8 (I am not familiar with Sybase at all so not sure whether that exists or not)