The problem occurs in both, the product and category names. Here is some code from the easy populate import file:

foreach ($langcode as $lang) {
if (!function_exists('mb_split')) {
// iso-8859-1
$categories_names_array[$lang['id']] = explode($categories_delimiter,$items[$filelayout['v_categories_name_'.$lang['id']]]);
} else {
// utf-8
$categories_names_array[$lang['id']] = mb_split(preg_quote($categories_delimiter), $items[$filelayout['v_categories_name_' . $lang['id']]]);
}