weblogic5.1下web application中如何从jsp调用bean和taglib（内详）

[wheels]

引入web application后，把自定义的class放到web-inf/classes下（当然，所有web.xml制定的servlet classpath都可以）这样做，servlet中引用不成问题，但是，在jsp中用usebean引用，我试了好多次，都不行，还有引用taglib也是不行，看过生成的中间.java文件，都被编译成beans.Beans.instantiate(getClass().getClassLoader(), "Gauge")
浏览报错
Compilation of 'D:\weblogic\myserver\classfiles\jsp_servlet\_jsp\_index.java' failed:
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D:\weblogic\myserver\classfiles\jsp_servlet\_jsp\_index.java:80: ???????????
probably occurred due to an error in /jsp/index.jsp line 4:
<jsp:useBean id="Gauge" scope="page" class="Gauge"/>

D:\weblogic\myserver\classfiles\jsp_servlet\_jsp\_index.java:80: ???????????
probably occurred due to an error in /jsp/index.jsp line 4:
<jsp:useBean id="Gauge" scope="page" class="Gauge"/>

D:\weblogic\myserver\classfiles\jsp_servlet\_jsp\_index.java:86: ???????????
probably occurred due to an error in /jsp/index.jsp line 5:
<%Gauge.maxValue=10; %>


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Tue May 29 16:42:36 CST 2001
请赐教