add_filter( 'gform_pre_render', 'add_notreadonly_script');
function add_notreadonly_script( $form ) {
	?>
	<script type="text/javascript">
		jQuery(document).ready(function(){
			jQuery("li.gf_notreadonly input").removeAttr("readonly");
		}
	</script>
	<?php
    return $form;
}