Experience based iConomy?

So I was looking around within the config.yml folder of iConomy when I noticed this:
# xp, exp, orb, xpdb, expdb, orbdb
# - These all equate to ExperienceDB, which relies on Experience for balance.
As an option for a database, I have tried replacing 'minibd' with 'ExperienceDB' but that just leads to errors when trying to check my balance... Perhaps I do not understand as to what it's saying, but when I read the description for ExperienceDB I thought it meant I could base my economy on experience and use it to buy things and gain it by selling things and killing mobs. So I ask is it that I have misunderstood or is there a bug at work? If I have misunderstood could someone point me in the direction of a plugin that could allow a experience based economy? And maybe tell me what these "databases" are?

Btw, I am using the newest stable build of iConomy; Celty.

 

I'm pretty sure it needs to be one of them that is in the line above. It says that 'These all equate to ExperienceDB...'. The list does not contain 'ExperienceDB'. Try one of these

 

I'm also interested in somehow using iconomy to function experience accumulated, creating choices and a market for experience on a survival server. Does iconomy natively support such a system, or has anyone created a plugin to do this?