Navigation, parent, children only display 1st level children of page.

Hi,

I am trying to only display the children NOT grandchildren of each page here is a menu structure:

Home
About
-Why
-Where
–Seattle
—Bellevue
—Georgetown
–Tacoma
–Bellingham
Products
-1
–1.1
—1.1.1
-2…

I am using

`if($post->post_parent)
$children = wp_list_pages(“title_li=&child_of=”.$post->post_parent.”&echo=0&depth=1″);
else
$children = wp_list_pages(“title_li=&child_of=”.$post->ID.”&echo=0&depth=1″);
if ($children) {
echo $children;
} `

which works great for first level but I need it to write out another menu for the childrens children when the original child is selected.