google app engine - How do I access EntityManager from within Grails service (JPA + GAE) -

i'm having trouble accessing entitymanager within grails service:

my setup follows...

• basic grails application appengine , gorm-jpa plugins
• default settings pretty everything. haven't touched resources.groovy, persistence.xml etc.

some things good...

• i able access entitymanager within controllers adding "def entitymanager".

but...

• i have service i'm trying access entitymanager from, however, "java.lang.illegalstateexception: entitymanager closed!" exception.

• is plugin closing entitymanager somewhere? need change scope of entitymanager somehow? there xml file need update ensure proper injection?

  class googlecalendarservice implements initializingbean {     void afterpropertiesset() {     }   
     def entitymanager      public oauthtoken getaccesstoken(user u) {        //can't access entitymanager here        entitymanager.newquery(...) //throws illegalstateexception    } 
    } 

one weird note: reason, if re-save service while jetty , running service able access entitymanager once. if click reload (and have controller access service again) service can no longer access entitymanager...

i guess right way use entitymanagerfactory, this:

import org.springframework.orm.jpa.entitymanagerfactoryutils  class googlecalendarservice implements initializingbean {     void afterpropertiesset() {      }      def entitymanagerfactory     entitymanager em      public oauthtoken getaccesstoken(user u) {         em = entitymanagerfactoryutils.gettransactionalentitymanager(entitymanagerfactory)         //do stuff em     } }