newbie: serializing deserializing nested custom object

[fabrizio picca]

This is my first post, i'm new to axis, so excuse the eventual oddness
of this question.

i wanna call a remote service like this

setTrigger(hashtable triggerMap,String urlRef,String ipRef)

The hashtable triggerMap contains  Trigger custom objects.

Those Triggers are made of String and another custom object : Event.
Event,in the end is made up of two strings and the last custom Object:
Parameter which contains only strings.

following the example found in axis documentation i've wrote down this:

QName    qnT      = new QName( endpoint , "Trigger" );
                        QName    qnP      = new QName( endpoint , "Parameter" );
                        QName    qnE      = new QName( endpoint , "Event" );

                         call.registerTypeMapping(Parameter.class, qnP,
                    new
org.apache.axis.encoding.ser.BeanSerializerFactory(Parameter.class,
qnP),
                    new
org.apache.axis.encoding.ser.BeanDeserializerFactory(Parameter.class,
qnP));
                         call.registerTypeMapping(Event.class, qnE,
                                new 
org.apache.axis.encoding.ser.BeanSerializerFactory(Event.class,
qnE),
                    new
org.apache.axis.encoding.ser.BeanDeserializerFactory(Event.class,
qnE));
                 call.registerTypeMapping(Trigger.class, qnT,
                        new
org.apache.axis.encoding.ser.BeanSerializerFactory(Trigger.class ,
qnT),
                        new
org.apache.axis.encoding.ser.BeanDeserializerFactory(Trigger.class,
qnT));

But all i  can obtain is an Exception like:

No Deserializer for {[endpoint]}Trigger.

I hope i was quite clear in explanation.
Tanks a lot.

Fabrizio