JDBC Adapter services dont always work

My JDBC adapter services seem to loose their ability to run if they are not used for a couple days. However, if I go and change anything with the adapter and save it, then they work again.

My solution has been to schedule services that run a basic query every 2 minutes to keep connections alive. This is all right for now with only about 10 running integrations, but in the future this will be a major hassle.
Is something not configured correctly? Pools, cache, stateless,TNSNAMES ???

By the way, I am running version 6.01.
Has this been improved in later releases?

I’m new to webmethods but I also spotted this behaviour:

If you stop\start the database, the connection is also lost. I wander if the Integration server hasn’t the ability to check if the connection is lost and restart another one (connection pooling)?