Adding attribute to body tag

[John]

Hi,

I need to add a class attribute to the body tag but this:
component.add(new AttributeAppender("class", true, Model.of("yui-skin- 
sam"), " "));

... and this ...

component.add(new BodyTagAttributeModifier("class", true,  
Model.of("yui-skin-sam"), component));

are not working.  Is there a new way to do this?

Thanks,

John