domino + servlet+Ajax：servlet接收到的数据有中文乱码？

servlet是在domino环境下运行的，中文乱码的原因应该是没有设置请求参数的编码方式：request.setCharacterEncoding("UTF-8")，但是我在servlet中加入这句代码之后，domino控制台便报如下错误信息：
HTTP JVM: java.lang.NoSuchMethodError: javax/servlet/http/HttpServletRequest.setCharacterEncoding(Ljava/lang/String;)V: javax/servlet/http/HttpServletRequest.setCharacterEncoding(Ljava/lang/String;)V

是不是domino下的servlet相关的jar包版本过低？不过我用的domino是8.0.2的版本。试着在notes.ini文件中引入servlet-api.jar还是报相同的错！大家一起帮忙想想有没有解决这个乱码的办法？

--------------------编程问答-------------------- IT500强企业职位推荐
Title:  IT Specialist - Onsite Support
Location: Beijing
Job Description:
- Onsite support or remote support for software product.
Candidate Requirements:
-3+ years implementation/administration/product support experience of at least one of the following products:
  1) WebSphere product, WAS certification is pre-request.
  2) Lotus product, Lotus certification is pre-request.
-Good communication skills, project management experience is a plus.
-Bachelor's Degree
-English: Fluent
Please email me with your recent Chinese and English CV if you have interest and need more details.
Karen
E-mail:karenlin@haxinternational.com
MSN:karen.shima@hotmail.com
Tel:010-58690411-823
--------------------编程问答-------------------- 简单的办法试试 , 在前台传参的时候把值用escape() 处理下。 --------------------编程问答-------------------- 中文，那么就在本地加编码，到servlet解码` --------------------编程问答-------------------- 用：response.setContentType("text/html; charset=utf-8");
开发中一定不能用：request.setCharacterEncoding("UTF-8")

补充：企业软件 ,  Lotus