generation Client stub using WSDL - error

[tctan]

I am working through a worksheet from the Web service revolution and is
getting an error using the WSDL to generate the CurrencyExchangeService
Client Stub.  The error msg given is:

Exception in thread "main" java.lang.NoClassDefFoundError:
org/apache/soap/util/xml/XMLParserLiaison at
com.ibm.wsdl.Main.main(Main.java:30)

has anyone come across this or can offer some advise?

cheers

TC