Section Editing Problem

Hi, I just switched from MediaWiki and installed XWiki 1.1m3, and I found section editing and collaborative editing one page in xwiki is not so well supported compared with MediaWiki. And I have several questions: (1) Instead of using h2 tag to automatically add a section editing icon, could I manually tag a paragraph as a section and edit it? (2) Even if I divide the whole page into several sections with h2 tag, when different users edit different sections in one page, xwiki still indicates someone locks the page, is it possible to get smaller lock granularity and lock just the section rather than the whole page? I think wiki is a collaborative tool, and editing one page in the same time is a very important functionality and should be well supported.Anysuggestion is appreciated, thanks. Regards,