Comment 1 for bug 540180

Just to add some information about this issue, you can configure C3P0 pool to check connections periodically:

http://www.mchange.com/projects/c3p0/index.html#configuring_connection_testing

Not sure about that, but maybe you just need to add the following property in you application.conf:

hibernate.c3p0.idleConnectionTestPeriod=5 #or any other number of seconds