Debugging mysql stored procedures

3 mounth ago I serfed web to find some kind of mysql stored procedure
debugger. But I found nothing.
Last week at last a tool with integrated debugger was released. MySql
Developer Studio 2.0 http://crlab.com/mysqldev/. It uses debug engine
like an oracle dbms_debug, and supports breakpoints, watches, call
stack, and stepping through code facilities. May be it can help you
developing complex stored routines