xerces exception : General Schema Error

[Net2property -- Quotation <qu...@net2property.com>]

Hi has anybody encounter and/or solved this problem :

The parser used is the default parser of Cocoon 1.8. The file name is "xerces_1_2.jar"

The following message is produce when the parser.validate value is changed to true.
(parser.validate = true) in cocoon.properties.

The webserver used is Jrun 3.0

java.lang.RuntimeException: org.xml.sax.SAXParseException: General Schema Error: Grammar with uri : http://www.w3.org/1999/XSL/Transform , can not found.
at org.apache.xerces.framework.XMLParser.reportError(XMLParser.java:1008)
at org.apache.xerces.validators.common.XMLValidator.validateElementAndAttributes(XMLValidator.java, Compiled Code)
at org.apache.xerces.validators.common.XMLValidator.callStartElement(XMLValidator.java, Compiled Code)
at org.apache.xerces.framework.XMLDocumentScanner.scanElement(XMLDocumentScanner.java, Compiled Code)
at org.apache.xerces.framework.XMLDocumentScanner$ContentDispatcher.dispatch(XMLDocumentScanner.java, Compiled Code)
at org.apache.xerces.framework.XMLDocumentScanner.parseSome(XMLDocumentScanner.java, Compiled Code)
at org.apache.xerces.framework.XMLParser.parse(XMLParser.java:900)
at org.apache.cocoon.parser.XercesParser.parse(XercesParser.java:84)
at org.apache.cocoon.parser.AbstractParser.parse(AbstractParser.java:83)
at org.apache.cocoon.processor.xsp.XSPProcessor.init(XSPProcessor.java, Compiled Code)
at org.apache.cocoon.framework.Manager.create(Manager.java:101)
at org.apache.cocoon.framework.Router.init(Router.java, Compiled Code)
at org.apache.cocoon.framework.Manager.create(Manager.java:101)
at org.apache.cocoon.Engine.(Engine.java:171)
at org.apache.cocoon.Engine.getInstance(Engine.java:218)
at org.apache.cocoon.Cocoon.init(Cocoon.java:141)
at allaire.jrun.servlet.JRunServletLoader.loadServletInstance(JRunServletLoader.java, Compiled Code)
at allaire.jrun.servlet.JRunServletLoader.loadServletInstance(JRunServletLoader.java:190)
at allaire.jrun.servlet.JRunServletLoader.loadServlet(JRunServletLoader.java:177)
at allaire.jrun.servlet.JRunSE.getServletReference(JRunSE.java:1261)
at allaire.jrun.servlet.JRunSE.runServlet(JRunSE.java, Compiled Code)
at allaire.jrun.servlet.JRunRequestDispatcher.forward(JRunRequestDispatcher.java:88)
at allaire.jrun.servlet.JRunSE.service(JRunSE.java:1131)
at allaire.jrun.servlet.JvmContext.dispatch(JvmContext.java:330)
at allaire.jrun.http.WebEndpoint.run(WebEndpoint.java:107)
at allaire.jrun.ThreadPool.run(ThreadPool.java, Compiled Code)
at allaire.jrun.WorkerThread.run(WorkerThread.java, Compiled Code)
at org.apache.cocoon.processor.xsp.XSPProcessor.init(XSPProcessor.java, Compiled Code)
at java.lang.Exception.(Unknown Source)
at java.lang.RuntimeException.(Unknown Source)
at org.apache.cocoon.processor.xsp.XSPProcessor.init(XSPProcessor.java, Compiled Code)
at org.apache.cocoon.framework.Manager.create(Manager.java:101)
at org.apache.cocoon.framework.Router.init(Router.java, Compiled Code)
at org.apache.cocoon.framework.Manager.create(Manager.java:101)
at org.apache.cocoon.Engine.(Engine.java:171)
at org.apache.cocoon.Engine.getInstance(Engine.java:218)
at org.apache.cocoon.Cocoon.init(Cocoon.java:141)
at allaire.jrun.servlet.JRunServletLoader.loadServletInstance(JRunServletLoader.java, Compiled Code)
at allaire.jrun.servlet.JRunServletLoader.loadServletInstance(JRunServletLoader.java:190)
at allaire.jrun.servlet.JRunServletLoader.loadServlet(JRunServletLoader.java:177)
at allaire.jrun.servlet.JRunSE.getServletReference(JRunSE.java:1261)
at allaire.jrun.servlet.JRunSE.runServlet(JRunSE.java, Compiled Code)
at allaire.jrun.servlet.JRunRequestDispatcher.forward(JRunRequestDispatcher.java:88)
at allaire.jrun.servlet.JRunSE.service(JRunSE.java:1131)
at allaire.jrun.servlet.JvmContext.dispatch(JvmContext.java:330)
at allaire.jrun.http.WebEndpoint.run(WebEndpoint.java:107)
at allaire.jrun.ThreadPool.run(ThreadPool.java, Compiled Code)
at allaire.jrun.WorkerThread.run(WorkerThread.java, Compiled Code)

Thanx.

With Regards,
Ryan Tey