How could refreshing a page cause future onClick() listeners to malfunction?

[Christopher Merrill]

I'm seeing problems throughout our app where refreshing the page causes
other event listeners to then malfunction. These are trivially simple
listeners, like:

Link customer_link = new Link("org_link")
    {
    @Override
    public void onClick()
        {
        setResponsePage(new
OrganizationAdministrationPage(getPageReference(),
_organization_key));
        }

    private static final long serialVersionUID = -6396556709778260098L;
    };


Instead of returning the response page, the browser receives a forward
(302) back to the same page instance...which of course means that the link
appears to do nothing.

I can only reproduce this behavior when the app is deployed to AppEngine --
it works fine running on my desktop. The problems started when we upgraded
the application to Wicket 6. I'm not implying this is a Wicket 6
problem...in fact I assume we have done something that is causing this
malfunction. But since it worked under Wicket 5, I'm hoping someone will
see a relationship between the symptoms and a change that we need to make
for compatibility with Wicket 6.

Any hints or debugging ideas (since I can't step through the code running
in AppEngine) would be greatly appreciated!

Chris