AS3 Error : #1009: Cannot access a property or method of a null object reference

Hi

I’ve been working on this flash project and having trouble with adding a new button selector:

public function selectColor(event:MouseEvent) : void
{
var _loc_2:* = “f” + event.currentTarget.chassisColor;
this.iColor_01.gotoAndStop(“fOff”);
this.iColor_02.gotoAndStop(“fOff”);
this.iColor_03.gotoAndStop(“fOff”);
this.iColor_04.gotoAndStop(“fOff”);
this.iColor_05.gotoAndStop(“fOff”);
this.iColor_06.gotoAndStop(“fOff”);
this.iColor_07.gotoAndStop(“fOff”);
event.currentTarget.gotoAndStop(“fOn”);
this.iChassis.gotoAndStop(_loc_2);
return;
}// end function

The debugger keeps crashing at this point: this.iColor_07.gotoAndStop(“fOff”);

[FONT=Verdana]The full project is here if you would like to see it in context:
[/FONT]http://dl.dropbox.com/u/19065571/help.zip
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