How to Set a Persistent Connection to Database with Zend Framework Zend_Db adapter

From time to time, it may be a good idea to have a persistent connection to database. The place where it should be added that new configuration option is application.ini ( DotKernel approach as an example) Do not try something like below, will not work:

>database.params.options.PDO::ATTR_PERSISTENT = TRUE

  Instead , use the below line

>database.params.persistent = TRUE