I'm not sure how to implement it without changing umbraco or yetanotherforum sources. I think is should be changable using web.config. Try play with google, this could be your starting point:

http://stackoverflow.com/questions/386131/keeping-viewstate-in-sessionpagestatepersister

Petr

As i understood from this solution, I only need to override PageStatePersister:

protected override PageStatePersister PageStatePersister
{
    get
    {
        return new SessionPageStatePersister(this);
    }
}

But where do I need to do it?

In umbraco or in forum? or I need to create base page and

After I create CustomPage with overwrited PageStatePersister, what I need to do after? Do I need to inherit all umbraco pages from this page or I need to intherit only content page ( to change templates) to use CustomPage?

problem solved

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