If you are getting error similar to above error, a slight modification on your /admin/reviews.php is needed to work better with php5.

find :
$review_info = array_merge($reviews_text, $reviews_average, $products_name);
$rInfo_array = array_merge($reviews, $review_info, $products_image);

replace :
$review_info = array_merge((array)$reviews_text, (array)$reviews_average, (array)$products_name);
$rInfo_array = array_merge((array)$reviews, (array)$review_info,
(array)$products_image);

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