Today's browsers (or HTML < 5) only support HTTP GET and POST, but to communicate RESTful one need PUT and DELETE too. If the workaround should not be to use Ajax, something like a hidden form field is required to overwrite the actual HTTP method.
Rails uses the following trick:
<input name="_method" type="hidden" value="put" />
Is there a possibility to do something similar with JAX-RS?
To quote Roy Fielding:
In any case, there are plenty of RESTful services that do nothing but GET and POST. The key is how those methods are used, not what methods are used. To give a specific example, what makes a wiki more or less RESTful is almost always determined by how it (ab)uses GET and sessions -- whether it uses PUT or POST for editing pages is sugar topping in comparison.
Emphasis is mine, taken from this post http://tech.groups.yahoo.com/group/rest-discuss/message/10746