[xwiki-users] Create custom object using URL get/post/put

I'm investigating how to use curl or ~like this to create custom object for application integration (it should be authenticated, which seems no problem). I'm studying http://platform.xwiki.org/xwiki/bin/view/Features/XWikiRESTfulAPI It is possible to retrieve custom object, but I couldn't find how to add them. How it could be done? Thanks in advance, Valdis