My suggestion was that you may want to make sure that your jQuery scripts and/or plug-ins are encoded as UTF-8. To do that, you would need to open and save each script file using UTF-8 encoding.
File encoding may not be the issue at all. I've been unable to tell from your post if the problem is with jQuery itself or with a plug-in script. Have you verified if jQuery is running at all in IE6? For example, create a new page and insert a simple jQuery action that would let you know if it's running (such as an alert message).
