yes, there is a MouseEvent for right click. its MouseEvent.RIGHT_CLICK or "rightClick". MouseEvent.RIGHT_CLICK will not be highlighted in the Flash CS3 IDE. at least it doesn't in mine, but the code does work.
ActionScript Code:
mc.addEventListener(MouseEvent.RIGHT_CLICK, rightClickHandler);
function rightClickHandler(evt:MouseEvent){
trace("Right Clicked");
}
of course, tracing doesn't work testing the app normally. press <ctrl><shift><enter> to run the debugger where it will trace the message.
for the most recent AIR (in Flash) documentation, go to
http://help.adobe.com/en_US/AIR/1.1/devappsflash/
and in regular livedocs flash documentation a

will be next to any property or method that is only available in Adobe AIR.
example:
http://livedocs.adobe.com/flash/9.0/...ouseEvent.html