More about creating a remote object and passing an argument to a cfc from Flex 3 can be found at my blog post, HERE

Create Result function that will handle what comes back from the cfc.

<mx:Script>

      <![CDATA[

            import mx.controls.Alert;

            import mx.rpc.events.FaultEvent;

            import mx.rpc.Fault;

            import mx.rpc.events.ResultEvent;

            private function result(evt:ResultEvent):void {

                  mygrid.dataProvider = evt.result;

            }

            private function fault(evt:FaultEvent):void {

                  Alert.show(evt.fault.message);                 

            }

      ]]>

</mx:Script>

The Source starts from your wwwroot folder on your server. in this expample, the name of my cfc is called "thecfc.cfc", my cfc is located in the folder "cfctest", which is on the wwwroot of my server. Note: case sensitive

<mx:RemoteObject id=”mycfc”

                  destination=”ColdFusion”

                  showBusyCursor=”true”

                  source=”cfctest.thecfc”

                  result=”result(event)”

                  fault=”fault(event)”>

</mx:RemoteObject>