Any reason why they are immutable? There's basically no way (that I found at least) to add new properties after the ContentResponse is created and it's created without properties by MimeResponseImpl.getResponse()... Maybe I'm not understanding the proper usage, but I'd like to be able to add properties to the ContentResponse dynamically after it's created (i.e. in HeaderInterceptor to inject header content). Ideas? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4136426#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...