SQLException: Can't call commit when autocommit=true

When my grails application faces high load, I encounter some SQLException : java.sql.SQLException: Can't call commit when autoc开发者_开发问答ommit=true

This problem appears only when the number of connection on the application raises.

I'm using grails 1.2.2 and mysql 5.1

Does anybody already faces such kind of problem ?

Thanks in advance.