I'm building an exchange for nxt, which aims to be trading/deposting/withrawing in automatic mode. But it seems like people can only send from one adddress to another rather than many-to-many like bitcoin, this will cause a huge transaction fee. 

so I'm wondering when will the official client support many-to-many transaction?  Is there a roadmap.

Hello everyone,
We are building a cryptocoin exchange platform, which is more easy, secure, fast.
I personally also have some good idea about bitcoin p2p exchange system.