Adding multiple MC's via a class

Hello, in my Doc Class I am trying to load in multiple MCs onto the stage which come from a class held in the library …
I get an error whilst trying to name them … perhaps it too much of an AS2 way? …If someone could help!>?
ps code is only a snippet of the problem…

for (var m:uint = 5; m > 0; m--) 
   //var obj:Item = new Item(200); this works - but I want to name each MC
   var ["thumb"+m]:Item = new Item(200);