Paste with empty clipboard inserts "null"

Flex 4.1

To reproduce :

Place cursor in textFlow, select nothing.

Copy

Paste

The text "null" is inserted instead of the expected "" empty string.

I've created a workaround, we can listen for paste events and manipulate the pasted content.

myTextFlow.addEventListener(FlowOperationEvent.FLOW_OPERATION_BEGIN, handleFlowEvents);

...

private function handleFlowEvents(e:FlowOperationEvent):void {

     if (e.operation is PasteOperation) {

trapPaste(e.operation as PasteOperation);

}

}

private function trapPaste(po:PasteOperation):void {

var pasteTxtflow:TextFlow = po.textScrap.textFlow

pasteTxtflow.interactionManager = new EditManager();

if (pasteTxtflow.mxmlChildren.length == 1 && pasteTxtflow.getFirstLeaf().text == "null" && pasteTxtflow.getFirstLeaf() is SpanElement) {

(pasteTxtflow.getFirstLeaf() as SpanElement).text = "";

return;

}

}