swapDepths Help!

Hi,

I am creating images animation & using attached movie. Movieclip used is “picMc”. I am using linkage to call the movie in the file

**Actionscript: **_root.attachMovie(“picMc”, “picBg”, 500);
I need that linkage file to be at the bottom of the file,
This movieclip curve should be on top of “picMc”.

[COLOR=#0066cc][COLOR=#000000]Actionscript: _root.cruve.swapDepths(2); _root.picMc.swapDepths(1);[/COLOR][/COLOR]

But it is not working.

_root.cruve.swapDepths(_root.picMc);

This too is not working. Please Help!