tiny_mce and the integration into xwiki

Hi all. At the moment I am looking into problems exists with xwikis wysiwyg editor. For instance, it is not possible to save the result of image operations in the wiki page. I have created an jira - http://jira.xwiki.org/jira/browse/XWIKI-906 - to update tiny_mce to most recent version. But know I need more informations, where, how, ... tiny_mce is integrated in xwiki. Where can i find the setup of tiny_mce... I hope somebody can help me, Christian