Class path problem

[nitish kumar sinha]

HI 
Could any one help me.
I want ot  convert the XML to PDf using XML-FO .I have included the
fop.jar,lib;avalon-framework-cvs-20020315.jar,batik.jar,
xalan-2.3.1.jar,xercesImpl-2.0.1.jar,xml-apis.jar in my classpath.Even i am 
getting the error 
Exception in thread "main" java.lang.NoClassDefFoundError: 
org/apache/avalon/framework/logger/Logger
        at XmlToPdf.main(XmlToPdf.java:24)
Could any one tell what is more required in the calss path.