confused over use of Web Service Broker

Hi,
I am using Web service broker pattern to interface with a system which has exposed its functionality through Web services . There can be many web services but I have just exposed one method in the WebServiceBroker implementation i.e invokeService(serviceName,parameterList) .
Another alternative I could think is to provide seperate methods in WebServiceBroker which can be used by bisiness methods , but doing so is giving an impression of WebServiceBroker being a businessdelegate and this also decrease the flexibility as each time a new service is added the WebServiceBroker interface needs to be changed .
Can some one suggest me if there is anything wrong with the first approach .

Thanks and Regards,
Chiku

I've researched this topic when I was doing my assignment.
I think that your are mixing up Proxy and Web Service Broker. Web Service Broker is basically a class which acts as an endpoint for web service, which methods are invoked after a web service request is processed. And Proxy may be used when you need to wrap other system web service calls into some class (I think it's your case)

so the methods in the proxy will be similar to business delegate ( most of them ), are there any other patterns which can be used in above cases .

yes, they will be similar, but business delegate is designed to be presentation layer pattern, and Proxy is in the business logic.
Check out the thread I've started some time ago, it's almost the same question as you ask:
http://www.coderanch.com/t/483154/Architect-Certification-SCEA/Session-Facade-Business-Delegate-Client