[wp-hackers] wp_list_pages

[Aaron D. Campbell]

I'm trying to display only top level pages AND pages that are either 
children of the current page, or children of the ancestors of the 
current page.  So, if I have a page structure like this:
A
 > R
 > > U
 > > > X
 > > > Y
 > > > Z
 > > V
 > > W
 > S
 > T
B
 > P
C
 > Q
D
E
F


On the main page, I'd like to display all the top level pages: A, B, C, 
D, E, F

On page 'A' I would like to display:
A
 > R
 > S
 > T
B
C
D
E
F

On page 'R' I would like to display:
A
 > R
 > > U
 > > V
 > > W
 > S
 > T
B
C
D
E
F

On page 'U' I would like to display:
A
 > R
 > > U
 > > > X
 > > > Y
 > > > Z
 > > V
 > > W
 > S
 > T
B
C
D
E
F

Basically, it would be like an expanding tree, but it would not use 
javascript, it would simply build the menu based on the current page.  
It seems like this would be a common desire.  Is there something like 
this out there, or some simple way of doing it?