navcolumntwo change position

Hello all,
My website behaves abnormal,
when i don't add productDetailsList,which is product by:at last in the center, then the navcolumtwo will change its position.
any clue guys?
this is the page

w w w .d e r m b a b y.com/testserver/index.php?main_page=product_info&products_id=3061
thank you very much

Hello all,
I would like to ask something related to my site's display, I am not so sure if its a css isse or php issue.
When i don't add the product with a manufacturer name, the position of the left column changes like this

w w w .d e r m b a b y.com/testserver/index.php?main_page=product_info&products_id=3061

If I add the product to manufacturer list,
then it shows
w w w .d e r m b a b y.com/testserver/index.php?main_page=product_info&cPath=134&products_id=3065
thank you very much