[xwiki-devs] how to debug hibernate error at profile save?

Hello XWiki exports, I've been working on a tool to massively import users from a spreadsheets for curriki.org (still on xwiki 3.5.1) and I am stumbling into an error that I could not solve thus far: (user-name is invented) The users element is that of the xwikiRights object. This exception happens at a saveandcontinue action which is triggered in the object editor after I (as admin) edit the user. It also happens if the user is logged in. How can I investigate this? I've tried changing the way I write the object in the following (adding the "new String") as it was done in the social-login but still no hope: def rightobj = userDoc.newObject("XWiki.XWikiRights", xcontext); rightobj.setStringValue("users", new String(userName)); rightobj.setStringValue("allow", new String("1")); rightobj.setStringValue("levels", new String("edit")); rightobj.setStringValue("groups", new String("")); Note: at curriki, we use the "virtual xwikiUsers group" since we have quite an amount of them. Any investigation hint is welcome. paul