src/main/java/org/efaps/ui/wicket/components/FormContainer.java
@Override
    protected void onComponentTag(final ComponentTag _tag)
    {
        if (this.actionUrl == null) {
            this.actionUrl = urlFor(getRequestCycle().getActiveRequestHandler()).toString();
        }
        super.onComponentTag(_tag);
        if (getPage().getDefaultModelObject() != null) {
            // only on SearchMode we want normal submit, in any other case we
            // use AjaxSubmit
            if (getPage().getDefaultModelObject() instanceof AbstractUIObject
                            && !((AbstractUIObject) getPage().getDefaultModelObject()).isSearchMode()) {
                //_tag.put("onSubmit", "return false;");
                _tag.put("action", "");
            }
        }
    }
@Override
    protected void onComponentTag(final ComponentTag _tag)
    {
        if (this.actionUrl == null) {
            this.actionUrl = urlFor(getRequestCycle().getActiveRequestHandler()).toString();
        }
        super.onComponentTag(_tag);
        if (getPage().getDefaultModelObject() != null) {
            // only on SearchMode we want normal submit, in any other case we
            // use AjaxSubmit
            if (getPage().getDefaultModelObject() instanceof AbstractUIObject
                            && !((AbstractUIObject) getPage().getDefaultModelObject()).isSearchMode()) {
                //_tag.put("onSubmit", "return false;");
                _tag.put("action", "");
            }
        }
    }
On component tag.

@param _tag the tag

@see org.apache.wicket.markup.html.form.Form
#onComponentTag(org.apache.wicket.markup.ComponentTag)