ReadPixels locks up webplayer when loaded via https...

We are encountering a problem with the ReadPixels() function when used in a webplayer loaded over an https connection. Here is the code:

 texture_to_display = new Texture2D (Screen.width, Screen.height, TextureFormat.RGB24, false);
 
 // put buffer into texture
 // THIS LINE LOCKS THE WEBPLAYER IN HTTPS
 texture_to_display.ReadPixels(Rect(0.0, 0.0, Screen.width, Screen.height), 0.0, 0.0,false);

 texture_to_display.Apply();

The function works fine when the webplayer is loaded over a standard http connection.

Any ideas what might cause this and more importantly, how to work around/fix it?

Thanks!