Form with just checkboxes does not allow to switch all off?!?

Hello there,

I've got this kind of form:

<wo:form action =3D "$app.emptyAction">
  Check
  <wo:checkbox checked =3D "$auctionTemplate.hiddenForOwner" onchange =3D =
"this.form.submit();" /> hidden for owner=20
  <wo:checkbox checked =3D "$auctionTemplate.hiddenForBroker" onchange =3D=
 "this.form.submit();" /> hidden for broker
</wo:form>

where app.emptyAction is truly an empty action (no contents, returns =
null), and it works excellently -- unless the last of the switches =
(regardless which one) is to be switched off.

In that case, the form properly reloads, but auctionTemplate is _not_ =
changed at all -- the application is _not_ informed about the change, =
and the hiddenForXXX property stays on.

Just by chance, I've found that if I add a completely unused variable =
'wtf' to the component and change the form thus:

<wo:form action =3D "$app.emptyAction">  ### action which does nothing =
at all
  Check
  <wo:checkbox checked =3D "$auctionTemplate.hiddenForOwner" onchange =3D =
"this.form.submit();" /> hidden for owner=20
  <wo:checkbox checked =3D "$auctionTemplate.hiddenForBroker" onchange =3D=
 "this.form.submit();" /> hidden for broker
  <wo:hidden value =3D "$wtf"/>
</wo:form>

it works quite all right.

What the heck?!? Is that a known bug in HTML or WebObjects or...what? Or =
is there some weird problem in my code somewhere?

Thanks and all the best,
---
Ondra =C4=8Cada
OCSoftware:     [email protected]               http://www.ocs.cz
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