Is it possible to change browser mode without using IE developer tools?

Our application works great in IE7 and IE8. We use the header X-UA-Compatible

to force the browser to use IE7 document mode. It is about which rendering engine afai will use to get the image. However, there are a lot of things in IE9 that stopped working. In IE9, Document Mode is IE7 standards, but Browser Mode remains IE9. When I manually change the browser mode (using developer tools) in IE7 everything is fine again.

Is there a way to programmatically force BROWSER MODE?