[PHP] Array question - Finding the name

[Phil Schwarzmann]

Let's say I have an array...

$my_array[] = array('bob' => $x,  'jim' => $y, 'mike' => $z);

Now I want to find the name of the second element in the array (I want
my result to be 'jim')

How do I do this?  I think I might have to use the key() function but I
can't quite get it to wkr.

Thanks!