Unwanted PHP notice on the frontend

I get a PHP notice on all frontend pages (WP 3.5.2, latest plugin version)…

Notice: Undefined offset: 1 in **********/wp-content/plugins/lockdown-wp-admin/lockdown-wp-admin.php on line 571

It’s because exploding the request url doesn’t always return a second item in the array. To fix it, you could do…

lockdown-wp-admin.php, Line 571
from…

list( $base, $query ) = explode( '?', $request_url, 2 );

to…

$vars = explode( '?', $request_url, 2 );
if( count( $vars ) == 2 )
  list( $base, $query ) = $vars;
else
  $base = $vars[0];

https://www.ads-software.com/extend/plugins/lockdown-wp-admin/