By default netbeans 6.9 is not providing the support for haml. We need to download the netbeans haml plugin and add to your netbeans.
Download the haml plugin from here:
then go to your netbeans Tools/plugins/ and go to Downloaded tab, click on add plugin select the drop down and give your downloaded plugin path. Click on ‘OK’ button. Click on ‘Install’. Thats it!