急救啊！！！HTTP Status 500 错误，网上查了很多还是不大明白，请大侠指点

HTTP Status 500 -

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type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: /conn.jsp(3,16) quote symbol expected
org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:40)
org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:407)
org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:88)
org.apache.jasper.compiler.Parser.parseAttribute(Parser.java:204)
org.apache.jasper.compiler.Parser.parseAttributes(Parser.java:149)
org.apache.jasper.compiler.Parser.parsePageDirective(Parser.java:360)
org.apache.jasper.compiler.Parser.parseDirective(Parser.java:493)
org.apache.jasper.compiler.Parser.parseElements(Parser.java:1568)
org.apache.jasper.compiler.Parser.parse(Parser.java:132)
org.apache.jasper.compiler.ParserController.doParse(ParserController.java:212)
org.apache.jasper.compiler.ParserController.parse(ParserController.java:101)
org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:156)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:296)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:277)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:265)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:564)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:302)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)


note The full stack trace of the root cause is available in the Apache Tomcat/5.5.27 logs.


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Apache Tomcat/5.5.27
问题1：这问题说的是什么意思，刷新conn.jsp，有时不会报上面的错误，有时有会这是什么原因哦，
问题2：下面是我conn.jsp的代码
<%@ page language="java" contentType="text/html; charset=GBK"
pageEncoding="GBK"%>
<%@page import=java.sql.* %>//如果这地方我不导入任何包的话下面name会出正确的结果，结果是4，但是当我导入这个包以后我在把name换成5的话，会报上面的错误。当我刷新以后有会显示出来结果但是结果并不是5而是上次的4这是什么原因啊，又刷新又报错，在刷又出结果还是4，搞了一下午硬是搞不明白，晕了，

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GBK">
<title>Insert title here</title>
</head>
<body>
<%
String name = "4";

%>
<%=name %>


</body>
</html>