With Firefox 3.0, or whatever their newest update was, they teamed with Google to show people a page that said a certain site may be a "Suspected Attack Site". Many warriors had their sites hit with this. My own mail servers were stopping me from checking my email.

To turn this "feature" off go to:
Tools > Options > Security and then uncheck the box that says "Tell me if the site I'm visiting is a suspected Attack Site."

Bingo,...