[Plugin: Polylang] (fix for) adjacent post function not working with v.0.6

I have installed WP 3.3.1 with a child theme of Twentyeleven, Theme Extensions plugin (for Twentyeleven theme) and Polylang v.0.6 .
While having just 2 posts for each language, I found an error log on the server (shared hosting) showing a MySQL error:

WordPress database error You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'ON object_id = ID WHERE post_type = 'post' AND post_status = 'publish' AND term_' at line 1 for query SELECT YEAR(post_date) ASyear, MONTH(post_date) ASmonth, count(ID) as posts FROM wp_posts INNER JOIN ON object_id = ID WHERE post_type = 'post' AND post_status = 'publish' AND term_taxonomy_id = 3 GROUP BY YEAR(post_date), MONTH(post_date) ORDER BY post_date DESC made by require, require_once, include, get_sidebar, locate_template, load_template, require_once, dynamic_sidebar, call_user_func_array, WP_Widget->display_callback, WP_Widget_Archives->widget, wp_get_archives

So, I have searching into the code and I found a missing globalize of the class $wpdb around the line 432, file core.php (/polylang/include/core.php).
To fix the problem I have added a line
global $wpdb;
just before this line
return $sql . $GLOBALS['wpdb']->prepare(" INNER JOIN $wpdb->term_relationships ON object_id = ID");
so the complete code of this function is now:

// modifies the sql request for wp_get_archives an get_adjacent_post to filter by the current language
	function posts_join($sql) {
                global $wpdb;
		return $sql .  $GLOBALS['wpdb']->prepare(" INNER JOIN $wpdb->term_relationships ON object_id = ID");
	}

Maybe it helps…

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