servlet中保存cookie时不能将其值设置成中文字符串？

simonhuan

比如：
Cookie username=new Cookie("name","张三");
response.addCookie(username);
当在浏览器中访问这个servlet时提示有异常：
HTTP Status 500 -

type Exception report

message

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

exception

java.lang.IllegalArgumentException: 张三
        org.apache.tomcat.util.http.ServerCookie.maybeQuote(ServerCookie.java:276)
        org.apache.tomcat.util.http.ServerCookie.appendCookieValue(ServerCookie.java:209)
        org.apache.coyote.tomcat5.CoyoteResponse.addCookie(CoyoteResponse.java:950)
        org.apache.coyote.tomcat5.CoyoteResponseFacade.addCookie(CoyoteResponseFacade.java:291)
        coreservlets.RegistrationServlet.doGet(RegistrationServlet.java:43)
        javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
        javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
        org.apache.catalina.servlets.InvokerServlet.serveRequest(InvokerServlet.java:419)
        org.apache.catalina.servlets.InvokerServlet.doGet(InvokerServlet.java:133)
        javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
        javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

note The full stack trace of the root cause is available in the Apache Tomcat/5.0.30 logs.
使用英文字符就没问题？谁遇到过吗？