[Plugin: Sociable] Fatal error in admin

Appears on the site:

Warning: array_key_exists() [function.array-key-exists]: The second argument should be either an array or an object in …/wp-content/plugins/sociable/sociable.php on line 133

When I try to access the admin plugin appears the error:
Fatal error: Cannot unset string offsets in …/wp-content/plugins/sociable/includes/sociable_output.php on line 91

what can this be?

http://ww.wp.xz.cn/extend/plugins/sociable/