If you have a table with table-layout:fixed and one of the cells have width:100% the rendering is compromised by the other cells widths.
It is quite difficult to explain in words. The provided URL shows the problem clearly.
It works correctly with Firefox, Opera and IE.
This bug breaks the rendering of the combos in the FCKeditor toolbar.
Created attachment 12332 [details]
Fixed table layout is hosed. Fixing bug 12115 should take care of it.
*** This bug has been marked as a duplicate of 12115 ***