Hello,
for other visitors:
It helped to add this code:
<browsers>
<browser refID="Default">
<controlAdapters>
<adapter controlType="System.Web.UI.HtmlControls.HtmlForm" adapterType="CMS.OutputFilter.HtmlFormAdapter" />
</controlAdapters>
</browser>
<browser refID="IE6to9">
<capabilities>
<capability name="supportsMaintainScrollPositionOnPostback"
value="false" />
</capabilities>
</browser>
</browsers>
to the default outputfilter.browser file (in the App_Browsers folder).
Best regards,
Helena Grulichova