Apache Tomcat 7.0启动错误

在启动Apache Tomcat 7.0 时，发生了这样的错误：May 30, 2011 11:06:36 AM org.apache.catalina.core.AprLifecycleListener init
INFO: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Program Files\Apache Software Foundation\Tomcat 7.0\bin;.;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\
May 30, 2011 11:06:36 AM org.apache.tomcat.util.digester.Digester startElement
SEVERE: Begin event threw error
java.lang.NoClassDefFoundError: javax/net/ssl/KeyManagerFactory
at org.apache.tomcat.util.net.AbstractEndpoint.<init>(AbstractEndpoint.java:622)
at org.apache.tomcat.util.net.JIoEndpoint.<init>(JIoEndpoint.java:53)
at org.apache.coyote.http11.Http11Protocol.<init>(Http11Protocol.java:71)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at java.lang.Class.newInstance0(Class.java:355)
at java.lang.Class.newInstance(Class.java:308)
at org.apache.catalina.connector.Connector.<init>(Connector.java:75)
at org.apache.catalina.startup.ConnectorCreateRule.begin(ConnectorCreateRule.java:62)
at org.apache.tomcat.util.digester.Digester.startElement(Digester.java:1282)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:501)
at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:179)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1343)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2755)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:648)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1543)
at org.apache.catalina.startup.Catalina.load(Catalina.java:554)
at org.apache.catalina.startup.Catalina.load(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.load(Bootstrap.java:262)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:430)
Caused by: java.lang.ClassNotFoundException: javax.net.ssl.KeyManagerFactory
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
... 32 more
请各位帮忙，我重新安装Tomcat 好几次都这样，不能启动-Dcatalina.home=C:\Program Files\Apache Software Foundation\Tomcat 7.0
-Dcatalina.base=C:\Program Files\Apache Software Foundation\Tomcat 7.0