I've updated to 4, as you advised, so no longer have the issue but I still think users have varied reasons for keeping old versions on their machines and it is their decision whether to update or not, hence the setting they can adjust. It is an unacceptable precedent to adjust it for them after an update without their knowledge, it reminds me of Flash cookies several years ago which were secretly hidden away on your system until detected by users and the excuse was they were there because "users don't understand cookies" whereas I think in most cases users understood all too well what cookies did and weren't too keen to have them used for tracking...