persistent zval

Hi all, Is it possible to make a zval persistent? Currently I only found persistent resources or internal references used in objects. It would be very great for some userland applications to make a value persistent whatever type it is. Like the internal global "persistent_list" but this one is used for persistent resources and I don't see how to use this one for zval's directly. Additionally it's used internally with unknown hashes so it could be dangerous to export it to userland. Marc