tomcat server配置
<Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true"
maxThreads="150" scheme="https" secure="true"
clientAuth="false" sslProtocol="TLS"
keystoreFile="d:/cas/zs/root.keystore" keystorePass="mh198406*"
/>
运行客户端时可以跳到csa登陆界面，输入用户名和密码后就报错
java.lang.RuntimeException: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
org.jasig.cas.client.util.CommonUtils.getResponseFromServer(CommonUtils.java:341)
org.jasig.cas.client.util.CommonUtils.getResponseFromServer(CommonUtils.java:305)
org.jasig.cas.client.validation.AbstractCasProtocolUrlBasedTicketValidator.retrieveResponseFromServer(AbstractCasProtocolUrlBasedTicketValidator.java:50)
org.jasig.cas.client.validation.AbstractUrlBasedTicketValidator.validate(AbstractUrlBasedTicketValidator.java:207)
org.jasig.cas.client.validation.AbstractTicketValidationFilter.doFilter(AbstractTicketValidationFilter.java:169)
org.jasig.cas.client.authentication.AuthenticationFilter.doFilter(AuthenticationFilter.java:116)
org.jasig.cas.client.session.SingleSignOutFilter.doFilter(SingleSignOutFilter.java:76)
其他的操作都是安装网上教程走下来的，就走到这一步出错了，实在搞不明白，求高手指点下
补充：
证书信息：
CN=localhost,OU=webber,0=webber......
没有过期
证书已经导入到C:\Java\jdk1.6.0_10\jre\lib\security，而且tomcat是安装版的，用的是证书导入的jre
------解决方案--------------------------------------------------------
确认下C:\Java\jdk1.6.0_10\jre\lib\security\cacerts中是否存在你己经导入的证书信息