OK. Blank entries means that as date is passed in and validated via forms, it is then entered into $_SESSION so data can be persistent as the user goes back and forth. These values are eventually entered into the database and are blank, whereas the few values that are entered from $_POST (ie credit card numbers that I don't want to carry around in the session) are fine. The system works in IE7, FF and Opera and has also worked on my local version of IE6. I have created a session name and send the Cache-control:private header, which fixed similar issues in the past, but no success in this case.
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