Ajax + VRaptor + fileupload

E o seguinte e consigo enviar um formulario via ajax tipo

jQuery.fn.adicionaPessoa = function(){
jQuery.ajax({
contentType: “application/x-www-form-urlencoded”,
async: true,
type: “POST”,
url: “cadpesssoa.adiciona.logic”,
data: (jQuery(’#formulario’).serialize()),
});
}

Isso ai em cima funciona blz.

Agora seu eu quiser usar o FileUpload como manda na documentacao no VRaptor ENCTYPE=“multipart/form-data”
o codigo ficaria assim
jQuery.fn.adicionaPessoa = function(){
jQuery.ajax({
contentType: “multipart/form-data”,
async: true,
type: “POST”,
url: “cadpesssoa.adiciona.logic”,
data: (jQuery(’#formulario’).serialize()),
});
}

tenho a seguinte exception:

java.lang.NullPointerException
at br.inf.atena.hibernate.logic.PeesoaLogic.adiciona(PesDigitalLogic.java:48)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.vraptor.component.DefaultLogicMethod.execute(DefaultLogicMethod.java:61)
at org.vraptor.interceptor.ExecuteLogicInterceptor.intercept(ExecuteLogicInterceptor.java:32)
at org.vraptor.core.InterceptorsLogicFlow.execute(InterceptorsLogicFlow.java:72)
at org.vraptor.interceptor.SettingAndValidationInterceptor.intercept(SettingAndValidationInterceptor.java:131)
at org.vraptor.core.InterceptorsLogicFlow.execute(InterceptorsLogicFlow.java:72)
at org.vraptor.interceptor.InjectionInterceptor.intercept(InjectionInterceptor.java:41)
at org.vraptor.core.InterceptorsLogicFlow.execute(InterceptorsLogicFlow.java:72)
at org.vraptor.interceptor.ComponentLookupInterceptor.intercept(ComponentLookupInterceptor.java:58)
at org.vraptor.core.InterceptorsLogicFlow.execute(InterceptorsLogicFlow.java:72)
at org.vraptor.interceptor.MultipartRequestInterceptor.intercept(MultipartRequestInterceptor.java:71)
at org.vraptor.core.InterceptorsLogicFlow.execute(InterceptorsLogicFlow.java:72)
at org.vraptor.interceptor.FlashScopeInterceptor.intercept(FlashScopeInterceptor.java:22)
at org.vraptor.core.InterceptorsLogicFlow.execute(InterceptorsLogicFlow.java:72)
at org.vraptor.interceptor.RegisterAttributesInteceptor.intercept(RegisterAttributesInteceptor.java:38)
at org.vraptor.core.InterceptorsLogicFlow.execute(InterceptorsLogicFlow.java:72)
at org.vraptor.core.VRaptorExecution.execute(VRaptorExecution.java:98)
at org.vraptor.core.DefaultController.execute(DefaultController.java:46)
at org.vraptor.VRaptorServlet.service(VRaptorServlet.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.displaytag.filter.ResponseOverrideFilter.doFilter(ResponseOverrideFilter.java:125)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Unknown Source)

Ou seja a imagem que esta para fazer download faz com que via ajax de pau se eu usar o botao submite do form para enviar os dados nao da pau.
Como se resolve isto preciso enviar via ajax e nao com o botao submite do form.

Obrigado !!!
Joao Vitor