spring - Format JodaTime LocalDate in SpringMvc JSON using formatter -

i have problem spring application.
how can format localdate in json...
problem when send json have send number, when spring generate json have:

"data": {     "weekyear": 1970,     "weekofweekyear": 1,     "chronology": {         "zone": {             "fixed": true,             "id": "utc"         }     },     "monthofyear": 1,     "yearofera": 1970,     ...and lot more 

i have field annotation datetimeformat like:

@datetimeformat(pattern="dd/mm/yyyy") private localdate data; 

and configurated format service in servlet-context.xml:

<beans:bean id="conversionservice" class="org.springframework.format.support.formattingconversionservicefactorybean">  </beans:bean> 

but alone doesn't work, miss configure?