BTW the last two images are not in their container in IE6
The last two images in that block are misplaced in IE6 because you haven't defined a class for the middle spacer img to occupy. You have left the class as container5 but nothing is defined. Change it to .spacerimg and add a style similar to this:

.spacerimg {
OVERFLOW: hidden; 
WIDTH: 100%; 
HEIGHT: 67px
That should make it display ok in IE6.