Directory tree as an associative array?

[eluser]kyleect[/eluser]
Consider the following:

/
file1
/dir1
file1
/dir2
file1
file2

What I'd like to do is access this structure as an associative array:

Code:

echo $array['dir1']['file1'];
echo $array['dir2']['file2'];

I can figure out how to write the file contents from the files, the real issue I'm having is finding a native or non native php function for listing directories as an associative array.