SwapDepths() Problem

Hi everyone…this is an excerpt from the Flash MX 2004 Help file

[color=darkslateblue]SwapDepths()[/color]

[color=darkslateblue]Method; swaps the stacking, or z-order (depth level), of the specified instance (my_mc) with the movie clip specified by the target parameter, or with the movie clip that currently occupies the depth level specified in the depth parameter. Both movie clips must have the same parent movie clip. Swapping the depth level of movie clips has the effect of moving one movie clip in front of or behind the other.[/color]

[color=black]Im using this Actionscript to attempt to swapdepths mc’s using their levels, not names, since they are dynamic[/color]

[color=navy]this._parent.swapDepths(_root.stage_3_vars.villaNumberResults);[/color]

[color=black]And its not working. Why cant swapdepths accept my variable as a level number? It works perfectly if I just use a number like:[/color]

[color=#000080]this._parent.swapDepths(5);[/color]

Please enlighten me someone.