There's no frame.  You've got a table which holds the first copy of the top bar.  Then another table, which contains the left bar, the margin, the the data area, however, the data area has a second copy of the top and left bars.
Either remove the first table and the first cell of the second table, or remove the bars from the content area of the second table.
I'm not going to even try to do it myself - that html is too mangled.  Do you have firefox and firebug?  If not, get them.  It's inspect feature is perfect for fixing this kind of trouble.