what does required="true" means in case of checkbox ?
it should be onclick.
onchange is fired in IE only when the field is left
onclick, i tried, but it's the same result.
The most curious is the rendered html....no Ajax stuf at all !!
For the record, that was -as foreseen in my initial post- something I had done wrong !
I had replaced my JSF libs in Glassfish by hand, not using the installer jar they provide in JSF's download area.
I made it the proper way and it all worked perfect then.