Oh man!
I just solve the problem myself. In functions.php i replaced following:
<?php
if ( function_exists('register_sidebar') )
register_sidebar(array(
'before_widget' => '<li id="%1$s" class="widget %2$s">',
'after_widget' => '</li>',
'before_title' => '<h2 class="sidebartitle">',
'after_title' => '</h2>',
));
?>
With
<?php
if ( function_exists('register_sidebars') )
register_sidebars(2);
?>
and added a number 2. Now it show up in admin. ??
Dancing “happy dance”