No serializer found for class error

[Meir Yan]

Hello all
im beginner in web services I did simple class and convert it to web service stubs in client
my class is using my custom data structure that build of vector and in every vector element I have hashtable
any way when im invoking the method in my class on the server side every thing goinging well until it getting to the point
it has to return me to the client this custom datastructer: and it gives me this error :
AxisFault
faultCode: {http://schemas.xmlsoap.org/soap/envelope/}Server.userException
faultSubcode:
faultString: java.io.IOException: No serializer found for class com.mytest.datastructures.myCostomList in registry org.apache.axis.encoding.TypeMappingDelegate@e2fbeb
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I was reading about serializers and deserializers but I didn�t understand much , how can I map my costume data type so I could use it with my web service ?