Urgent-problem with check box

Hi,

I have a code were in I attach a movieclip called sym1,
this.attachMovie("sym1","sym2",this.getNextHighest Depth());

next I wanted to create 2 checkboxes for it,

sym2.createObject("Checkbox","ch1",this.getNextHig hestDepth());
sym2.createObject("Checkbox","ch2",this.getNextHig hestDepth());

when I create ch2,ch1 becomes undefined.
What should I do?
How should I create ch2 without deleting ch1.

Kindly help

Sorry sivanathan, this is beyond my AS capabilities. Try asking in actionscript.org.