Code:
[img link=http://img641.imageshack.us/img641/7220/calculatorr.jpg]http://img641.imageshack.us/img641/7220/calculatorr.th.jpg[/img]
I added a 'link=' tag to the img so you can designate a link to open when the image is clicked.
Now if you use the image icon to insert an image, the link tag will prepopulate and you can change it to the page you would like to go to whne it's clicked, regardless of the image location.
Obviously, this change is only affective from this point onward.