MPTtree, Hieararchical trees in a database table

[eluser]pistolPete[/eluser]
hi m4rw3r,

first of all thanks a lot for your comprehensive model!

i've got two questions:

i manage hierarchical pages using MPTtree, and i added a column "visible" to my table.
i am now trying to find the first VISIBLE leaf of the tree, whose parents are all VISIBLE itself.
how could i find it?

second question:
i want to echo a hierarchical menu (a <ul><li>... list) to access these pages, but in the menu should just be the pages, which are visible and whose parents are all visible.
is this possible?

thanks in advance,

peter