FF 3.0.10 avoids cookies very effectively when enable cookies box is unchecked. FF 3.6.8 does not have ability to avoid cookies when enable cookies box is unchecked. Web sites are able to over-ride unchecked cookies setting, and insert cookies in unlimited fashion. Are FF 3.6.7 through FF 3.6.10 able to avoid this cookie over-ride process by these visited web sites ? What is reason for this vulnerability open door in FF 3.6.8 ? Running on WIN XP system. When use FF 3.0.10 to go to same sites, there is no problem with cookies control. Thank you for your help.