upgrade from 0.984 to 1.0B3

Hi Everyone, I was trying to upgrade from 0.984 to 1.0B3, but to no avail. I found this thread: http://mail-archive.objectweb.org/xwiki-users/2006-12/msg00106.html But there are no answers there. If I just run 1.0B3 on the existing database, I get an exception (trace below). Somewhere i read that this could mean the database is corrupted. But I don't think so, it works fine with release 0.984. So, is there an official way to upgrade the database so I can keep all the articles ? Thanks, Lukas com.xpn.xwiki.XWikiException: Error number 3 in 0: Could not initialize main XWiki context Wrapped Exception: Error number 3201 in 3: Exception while saving document XWiki.XWikiPreferences Wrapped Exception: Could not execute JDBC batch update com.xpn.xwiki.XWiki.getMainXWiki(XWiki.java:223) com.xpn.xwiki.XWiki.getXWiki(XWiki.java:303) com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:96) org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) javax.servlet.http.HttpServlet.service(HttpServlet.java:689) javax.servlet.http.HttpServlet.service(HttpServlet.java:802) com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:121)