variables in target path?

I have been searching all over and cannot find a solution to this problem. It works fine when I hard code it but I am trying to get this to work with the for next loop. It apears that the variable arrays are giving me a problem. Whatever I try gives me "TypeError: Error #1010: A term is undefined and has no properties"

Code below:

var menuCurrentPos:Array = new Array(0,1,2,3,4,6);
var menuDefaultPos:Array = new Array(0,1,2,3,4,6);
var menuMCArray:Array = new Array("btnAbout_mc", "btnCustDes_mc", "btnMaint_mc", "btnLogos_mc", "btnWebDesign_mc", "btnHome_mc");

for (var i:Number = 0; i < menuMCArray.length; i++) {
trace("i: " + i + " " + menuMCArray.length + " " + menuMCArray + " " + menuCurrentPos);
this.menuTabs_mc.setChildIndex(menuTabs_mc.menuMCArray , menuCurrentPos);
menuTabs_mc.menuMCArray .addEventListener(MouseEvent.ROLL_OVER, buttonOver);
menuTabs_mc.menuMCArray.addEventListener(MouseEvent.ROLL_OUT, buttonOut);
}

Any suggestions would be appreciated.

Thanks