functions.php thing problem. cannot logout

Hi guys. i just developed a simple theme for my blog. when using my theme i stuck logged in and cannot logout. i know there is an issue with my functions.php cause i get warnings form this file in apache log. if i delete my cookies then i cannot login.
here is my functions.php: (took it from Twenty Ten!)

<?php add_action( 'after_setup_theme', 'myown_setup');

function myown_setup() {
	register_nav_menu('primary', 'Navigation Under the header' );
}

// Register widgetized areas
function myowntheme_widgets() {
	// Area 1, located at the top of the sidebar.
	register_sidebar( array (
		'name' => 'Primary Widget Area',
		'id' => 'primary_widget_area',
		'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
		'after_widget' => "</li>",
		'before_title' => '<h3 class="widget-title">',
		'after_title' => '</h3>',
	) );

	// Area 2, located below the Primary Widget Area in the sidebar. Empty by default.
	register_sidebar( array (
		'name' => 'Secondary Widget Area',
		'id' => 'secondary_widget_area',
		'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
		'after_widget' => "</li>",
		'before_title' => '<h3 class="widget-title">',
		'after_title' => '</h3>',
	) );
} // end myowntheme_widgets_init
add_action( 'widgets_init', 'myowntheme_widgets' ); ?>

cheers and happy holidays!