Error when access default page

Just downloaded the last version from ww.wp.xz.cn website (I believe is the 3.1.4, read it on the readme.txt).

Enabled the plugin, changed the access control on each page (in the WordPress Access Control widget).

When first acessing the home of my site (its configured to show a particular page, not the posts), I get this:

Fatal error: Call to undefined function is_user_logged_in() in C:\wamp\www\teste\wp-content\plugins\wordpress-access-control\wordpress-access-control.php on line 774
Call Stack
#	Time	Memory	Function	Location
1	0.0003	249440	{main}( )	..\index.php:0
2	0.0005	252960	require( 'C:\wamp\www\teste\wp-blog-header.php' )	..\index.php:17
3	0.0009	269800	require_once( 'C:\wamp\www\teste\wp-load.php' )	..\wp-blog-header.php:12
4	0.0014	281408	require_once( 'C:\wamp\www\teste\wp-config.php' )	..\wp-load.php:29
5	0.0021	372560	require_once( 'C:\wamp\www\teste\wp-settings.php' )	..\wp-config.php:90
6	1.2655	21300072	include_once( 'C:\wamp\www\teste\wp-content\plugins\wp-user-frontend\wpuf.php' )	..\wp-settings.php:195
7	1.2785	22423352	require_once( 'C:\wamp\www\teste\wp-content\plugins\wp-user-frontend\lib\attachment.php' )	..\wpuf.php:37
8	1.2785	22423480	WPUF_Attachment->__construct( )	..\attachment.php:176
9	1.2785	22423640	wpuf_get_option( )	..\attachment.php:12
10	1.2785	22423688	wpuf_settings_fields( )	..\settings-options.php:11
11	1.2822	22536584	wpuf_get_pages( )	..\settings-options.php:365
12	1.2822	22536768	get_pages( )	..\wpuf-functions.php:460
13	1.2838	22587440	apply_filters( )	..\post.php:3836
14	1.2838	22590512	call_user_func_array ( )	..\plugin.php:173
15	1.2838	22590544	WordPressAccessControl::get_pages( )	..\plugin.php:173

http://ww.wp.xz.cn/extend/plugins/wordpress-access-control/