First, I assume you’re working with IS 4.6 as there is no such thing as IS 4.0.6. The 500 Server error indicates that the service you were consuming had a problem. Not sure where the null pointer exception is occuring.
To troubleshoot, use one of the many freeware utilities to capture the soap message traffic to see what is being returned from the service you are consuming.
There are several service packs and fixes available for IS 4.6, some of which affect web services support. Be sure that you have the latest from Advantage.
Mark
#API-Management#webMethods#soa