StaleObjectStateException when using Grails dynamic scaffolding

I am using dynamic scaffolding to create quick out of the box controllers and views to administrate the domain objects (e.g. only visible for admins).

class EventController {
   static scaffold = true
}

Whenever I update a domain instance of Event and then want to view the updated version /event/show/{id} I get a StaleObjectStateException

2014-09-18 08:51:26,274 [http-bio-127.0.0.1-50000-exec-8] ERROR org.codehaus.groovy.grails.web.errors.GrailsExceptionResolver - StaleObjectStateException occurred when processing request: [PUT] /event/update/15
Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect) : [ch.silviowangler.zscsupporter.Event#15]. Stacktrace follows:
org.hibernate.StaleObjectStateException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect) : [ch.silviowangler.zscsupporter.Event#15]
    at ch.silviowangler.zscsupporter.EventController.$tt__update(script1410592579337609530153.groovy:65)
    at grails.plugin.cache.web.filter.PageFragmentCachingFilter.doFilter(PageFragmentCachingFilter.java:189)
    at grails.plugin.cache.web.filter.AbstractFilter.doFilter(AbstractFilter.java:63)
    at grails.plugin.springsecurity.web.filter.GrailsAnonymousAuthenticationFilter.doFilter(GrailsAnonymousAuthenticationFilter.java:53)
    at grails.plugin.springsecurity.web.authentication.RequestHolderAuthenticationFilter.doFilter(RequestHolderAuthenticationFilter.java:49)
    at grails.plugin.springsecurity.web.authentication.logout.MutableLogoutFilter.doFilter(MutableLogoutFilter.java:82)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)

This happens in production mode using MySQL database with second level cache turned off.

So here are my questions:

• Since I use dynamic scaffolding I cannot analyse the scaffolded code at runtime, right?
• Can anyone tell me where to start analysing or even fix this problem?

Update

The domain class looks like this:

class Event {

    Date startDate
    Date endDate
    String title
    String location
    String organizer
    String externalLink

    static constraints = {
        title maxSize: 100, nullable: false
        startDate nullable: false, attributes: [precision: 'minute']
        endDate nullable: true, attributes: [precision: 'minute']
        location nullable: false, maxSize: 50
        organizer nullable: false, maxSize: 30
        externalLink nullable: true, maxSize: 255, url: true
    }

    @Override
    public String toString() {
        return "Event:{id:${id}, title: ${title}, startDate: ${startDate?.format('dd.MM.yyyy HH:mm')}, endDate:${endDate?.format('dd.MM.yyyy HH:mm')}"
    }
}

The behaviour seems to be gone when upgrading to Grails 2.5.1.