This feature has been requested several times, and now we're implementing it:
http://www.twilightmu.com/jogexchange.html
You can now exchange JOGs on the website which is faster and easier than selling those JOGs in-game and then depositing the Zen into your ZenBank.
This way the Zen is directly deposited into your ZenBank and you can exchange as many as a full vault of JOGs at a time (min 1 JOG - max full vault).
~Enjoy!