Comment 1 for bug 530654

Actually, the page as sent has no active button. If one presses enter with MSIE without first selecting a button (e.g. by tabbing), neither button's data will be sent, and Mailman will resend the confirmation page.

The other browsers I tried (Firefox, Opera, Safari and Google Chrome) all send the data for the first submit button on the page. I reordered the buttons so this is the 'subscribe' rather than the 'cancel' button.