[S2] not including null-params in URL of GET-submitted form

[Pierre Thibaudeau]

Is there a way to avoid null-valued (or empty-valued) parameters to be
explicitely mentioned in the URL generated by a form submitted through the
GET method?

For instance, here's a form:

<s:form action="myAction" method="get">
    <s:textfield name="param1" />
    <s:textfield name="param2" />
    <s:submit />
</s:form>

If the user types "FOO" in the first textfield and nothing in the second,
the submitted URL will be something like:
http://myhost.com/myAction.action?param1=FOO&param2=

Can I get rid of the "param2=" part, which serves no purpose?

(The alternative would be to POST the method to an action that would merely
redirect to the desired action, dropping the undesired parameters along the
way.)