Can you help me with my BG img/no-Rpt bug?

Hi

Please take a look at http://www.lifeespana.com/2004/CSS%20index2.htm

Its the first CSS layout I have done and as far as I can tell it has gone reasonably well (so far!).

The biggest problem I have is (on IE6) when you scroll down the page so the first tab (Property sales) disappears off screen, and then scroll back up again a duplicate of the tab background image appears beneath it.
If you mouse over any of the links on the left it disappears. It doesn't do this in Opera of Firefox.

I would appreciate any ideas as to why its doing this, and any other feedback on the coding of the page.

Thanks in advance.

CC