Unbinding dates

[Paweusz]

I have method in my controller with following signature:
public static void list(@Valid Filter filter)
Class Filter contains field of type java.util.Date.

When I pass filter from controller to template in render method value of date is disassembled to all fields in Date class, so url looks like this:
http://localhost:9000/operators?orderBy=pesel&filter.employedFrom.defaultCenturyStart=0&filter.nip=&filter.street=&filter.login=&filter.employedFrom.serialVersionUID=7523967970034938905&filter.employedFrom.fastTime=1273829783432&filter.name=&filter.city=&order=ASC&filter.employed=true&filter.pesel=&page=1&filter.surname=&filter.employedFrom.ttb=14&filter.employedFrom.ttb=1&filter.employedFrom.ttb=0&filter.employedFrom.ttb=0&filter.employedFrom.ttb=0&filter.employedFrom.ttb=0&filter.employedFrom.ttb=0&filter.employedFrom.ttb=0&filter.employedFrom.ttb=0&filter.employedFrom.ttb=2&filter.employedFrom.ttb=3&filter.employedFrom.ttb=4&filter.employedFrom.ttb=5&filter.employedFrom.ttb=6&filter.employedFrom.ttb=7&filter.employedFrom.ttb=8&filter.employedFrom.ttb=9&filter.employedFrom.ttb=10&filter.employedFrom.ttb=11&filter.employedFrom.ttb=12&filter.employedFrom.ttb=13&filter.employedFrom.ttb=10000&filter.employedFrom.ttb=10000&filter.employedFrom.ttb=10000&filter.employedFrom.ttb=10300&filter.employedFrom.ttb=10240&filter.employedFrom.ttb=10360&filter.employedFrom.ttb=10300&filter.employedFrom.ttb=10420&filter.employedFrom.ttb=10360&filter.employedFrom.ttb=10480&filter.employedFrom.ttb=10420&filter.employedFrom.wtb=am&filter.employedFrom.wtb=pm&filter.employedFrom.wtb=monday&filter.employedFrom.wtb=tuesday&filter.employedFrom.wtb=wednesday&filter.employedFrom.wtb=thursday&filter.employedFrom.wtb=friday&filter.employedFrom.wtb=saturday&filter.employedFrom.wtb=sunday&filter.employedFrom.wtb=january&filter.employedFrom.wtb=february&filter.employedFrom.wtb=march&filter.employedFrom.wtb=april&filter.employedFrom.wtb=may&filter.employedFrom.wtb=june&filter.employedFrom.wtb=july&filter.employedFrom.wtb=august&filter.employedFrom.wtb=september&filter.employedFrom.wtb=october&filter.employedFrom.wtb=november&filter.employedFrom.wtb=december&filter.employedFrom.wtb=gmt&filter.employedFrom.wtb=ut&filter.employedFrom.wtb=utc&filter.employedFrom.wtb=est&filter.employedFrom.wtb=edt&filter.employedFrom.wtb=cst&filter.employedFrom.wtb=cdt&filter.employedFrom.wtb=mst&filter.employedFrom.wtb=mdt&filter.employedFrom.wtb=pst&filter.employedFrom.wtb=pdt

Way I want to use this construction in template is in link, for example:
<a href="@{testDate(filter)}">Test date</a>

Maybe date should be treated as primitive type in this situation?