Why is cakePHP trowing Blackhole after change "disabled" field via jQuery?

I have a form with a checkbox and 2 select boxes. I have a javacript/jQuery function that disables the select boxes onces the checkbox is selected:

function disable(id) {
    if($("#checkbox"+id).is(':checked')){
        $("#selectbox1"+id).prop('disabled',true);
        $("#selectbox2"+id).prop('disabled',true);
    }
    else {
        $("#selectbox1"+id).prop('disabled',false);
        $("#selectbox2"+id).prop('disabled',false);
    }
}

All is working well. However, when I check the checkbox and submit the form, the request is marked as "black-holed" However, the only thing that this function is changing is adding "disabled" to the <select> tags.

Anybody got an idea how to solve this?

disabled inputs aren't in POST data

As such, from the perspective of the server, selectively marking an input as disabled is the same as selectively removing it from the form - which would be detected as form tampering.

Possible solutions

Either don't disable that select, or, use unlockField to permit manipulating the select with javascript.