Pass a string to the index of an array

ok, i have a complex array that i have built out of the results from a database, and i am using strings to index the array instead of numerical values…

for example, i am indexing my array like this:

my_array["news"] = new Array();
my_array["news"][0] = "first news post";
my_array["news"][1] = "first news post";
my_array["news"][2] = "first news post";


so then, i want to basically call that array dynamically by feeding a variable into the index, like this:

ind = "news";
l = my_array[ind].length;

now when i do that, its not finding the array’s length, and i know this because my trace prints nothing, or undefined…so this tells me i can’t pass the string to the index of the array? how do i do this? there has to be a way??? i hope this question makes sense…i am desperate need of help here