Limiting what a Gift Certificate can be used for online

Hello,

We are looking at trying to sell gift memberships online and it has been suggested by our web developer that we sell a gift certificate masked as a gift membership; however, our developer cautioned us that this gift certificate could potentially be used to purchase tickets (or anything else we sell online).  This is something we would definitely not want to allow to happen.  Is there any way to restrict the gift certificate to only be used for memberships in Tessitura?  I have had a read through the documentation and it does say the following:

·        Gift certificates may be used towards single ticket purchases only (or subscriptions only, gifts only, etc).   An organization that handles tickets for several different groups may limit use of a gift certificate to only one.

For some reason I can't seem to find where the documentation states how to restrict this.  Has anyone managed to do this successfully?


Thanks,
Rathi