*UPDATE*

http://jsfiddle.net/6tH4E/

Working Fiddle... This fiddle produces the error if you follow the instructions

I have a form <div id="blah"></div>

ok so, I use the global block

$.block({ message: $('#blah'),onOverlayClick: $.unblockUI; }); // works

then when the form is submitted, I block the form

$('#blah').block({ message: 'Waiting...' });

on ajax completion

$('#blah').unblock();

this all works, however, once the form is unblocked, I can no longer click the overlay to close the parent form.... from the global block! HELP PLEASE