Well, isn't that the problem then? With quota on, you'll only see the diskspace left for that particular user, not for the entire disk. Wheter you check the properties of an ibay or the home directory doesn't make a difference; you'll always see the information of your quotum, nothing more.
Try to increase your quotum and see what happens. Keep in mind that files stored in an ibay, but with you as owner, also count for your quotum. It's the ownership that counts, not the location.
Michiel