getURL glitch with IE v7.

I glanced through the prior posts but didn't see anything on this subject.

I've run into an interesting "undocumented feature" of Microsoft Internet
Explorer version 7.

Here are the details:

1) I'm running a simple Flash presentation.
2) It's a .swf file running in the standalone Flash Player.
3) I have only two Actionscript commands; getURL to launch a website and
FSCommand(quit).
4) When the website comes up, it comes up twice; once as a tabbed window in
an already opened browser window and once in a new browser window.
5) This only happens in version 7 of IE. Older versions work as they should.

I haven't seen anything on this on the Microsoft site. Does anyone have any
thoughts, insight or experience with this glitch?

Thanks.