Mysql Connection Pooling Similar To PostgreSQL's PgBouncer
This started off as a comment but it's getting a bit long.

Perhaps you could provide a better description of what it is you actually want rather than simply say it's like something else.

If you want multiple clients to use the same connection, then it must be implemented in the DBMS, otherwise you have no session management. Further you need to advise how you intend dealing with issues of state spanning more than a single request/response (i.e. transactions).

It would also be helpful to know why you want it. MySQL has a very different setup cost and per-session overhead cost compared to PostgreSQL - why do you think it needs it, and why you think it would actually yeild any benefit.