[xwiki-devs] XEM installation problem

I installed XEM and getting the following error. Any idea why am i getting this? I guess there are no mysql connectivity problem since the database tables were created when I tried to instantiate the XEM. type Exception report message description The server encountered an internal error () that prevented it from fulfilling this request. exception javax.servlet.ServletException: 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:XWiki.XWikiPreferences Wrapped Exception: Failed to commit or rollback transaction. Root cause [] org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:535) org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:433) 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:621) javax.servlet.http.HttpServlet.service(HttpServlet.java:722) com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:129) com.xpn.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:152) com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:68) com.xpn.xwiki.web.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:304) com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:112) root cause 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:XWiki.XWikiPreferences Wrapped Exception: Failed to commit or rollback transaction. Root cause [] com.xpn.xwiki.XWiki.getMainXWiki(XWiki.java:402) com.xpn.xwiki.XWiki.getXWiki(XWiki.java:471) com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:136) com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:116) 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:621) javax.servlet.http.HttpServlet.service(HttpServlet.java:722) com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:129) com.xpn.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:152) com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:68) com.xpn.xwiki.web.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:304) com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:112)