The confirmation page for deleting attachments isn't displayed correctly in FF3.5.2 & IE7

Steps to follow to reproduce:

• create a new page and go to edit mode
• type some text
• click "Save & View"
• click on "Attachments" at the bottom of the page
• click "Browse"
• select an image from your computer and click "Open"
• click "Attach"
• after the image is attached click the red "X" button in order to delete it.

Results:

• in FF3.5.2: The confirmation message loads a couple of times before you can click "yes" or "no"
• in IE7 the confirmation page isn't displayed correctly (see attached image).